.. "Original coils with a MSD DIS 2 and a MSD tach adaptor … and I suggest it to anyone looking for an ignition upgrade. It really improved response and made the car pull much harder all the way to redline" Emmett Burke

The Miata ignition is a Mitsubishi part. The coil packs are exactly the same as found on the turbo Mitsubishi Eclipse.

The design of the OEM coils is tailored to a specific type of plug wire (inductive spiral core) that is sold as OEM and as NGK blue. These wires produce a lower-current but longer-elapsed-time spark than solid core wires produce with the OEM coils, but without the energy loss produced by resistive wires. Ray Ayala

These are the same plugs that HKS supply (i.e Denso make HKSs Iridium plugs). I tried these last year to see if they would help with my misfire problems at 15 psi. they did *slightly* and they are an OK plug in other respects, no noticeable power improvement though. Cost me £56 for 4! Won't buy them again at that price. I'm currently running NGK Gold palladiums (BCP 7EV) and am very pleased with them and at £30 for 4 they are cheaper. They are certainly as good as the Iridium's IMHO. Steve Willington

Vishnu does M2 1.8 and M1 1.6/1.8 versions, M2 is non return type.

Jim Bobowski makes a 99 fuel rail for $119.. j_bobowski@yahoo.com

0580-254-957 is HP Bosch fuel pump 500hp? $89

"Rough numbers? Numbers are guesses and greater/less than symbol indicates probable direction of reality.

>33% driveshaft power ( in Miata 115 hp or 90 kW)

<30% water radiator heat

<30% heat out exhaust pipe

>5% convection and radiation (ballpark: 18000 W)

<4% oil cooler (ballpark: 9000 W)

So let's say the oil cooler is 3% or 9 kW and the water radiator is 30 % or 90 kW. Then the oil cooler represents 9 / 90 = 10% of the cooling capacity." Lance Karl Schall

Hot oil will eat right through coolant hose. Silicone hose is also no good for oil. Your best bets are Teflon, Viton, Fluorosilicone or Nitrile (in order of preference).

Reference for everyone on Evans non aqueous coolant. I had an interesting tech day at a local race engine builders shop last Saturday. Evans came up as a cooling solution for hot running cars and was discussed in depth by people that have actually run in on the track *and* on the street for extended periods. Evans has changed their tune on the necessity of a high volume pump. Also some people found that a pressurized system worked better than a zero pressure system for their application. However, most found that removing the inner seal on the radiator cap to allow a zero pressure system worked better at cooling. Evans can now be considered a "drop in" coolant change. That said, you *must* get as much of the regular coolant out of the system first. Less than 3% water in absolutely necessary and less than 1% is much, much better. On trick for those not building a motor, and thus not having a dry block to start with, is to change to Sierra coolant and run just 100% Sierra for a couple of days, then change out the coolant again with 100% Sierra and run a couple of more days and drain. If it looks pretty good on draining, as in non contaminated, go ahead and put the Evans coolant in. While Evans DOES NOT mix with water or normal coolant, it DOES mix with the Sierra w/o problems. Still much better to get as much of the Sierra out too though. The purer the Evans the more efficient it will be. Another trick is to fab a fitting to the system so that you can apply vacuum to the coolant system. As you all remember, water will boil at lower temps, (like room temp), in a vacuum. You can get all of the water/coolant out this way if you have some patience and a vacuum device. I've heard that it can be done with a Mityvac, but can not verify that. (seems like it might be tough.) An a/c fitting and a shops a/c vacuum tools may work better. Everyone that had used the Evans in street and track applications was very pleased with the results. I was surprised to hear from a bunch of street guys as well as the track only guys that this stuff works fine on a day to day level. Warms up faster and there are no issues on the street with the exception of needing to carry your own spare coolant since you can't get it everywhere. Also, for us poor bastards that live in non self serve states, watch out for "helpful" service station people adding water to your system. The freezing point of Evans is below -70F. It becomes a slushy at -70F, but if the water pump will move it, it works fine when the engine warms it up. (So they say.) The Evans runs around $26 a gallon here. But if not contaminated, it will last indefinitely. Some of the locals were running the same originally installed coolant for over 5 years with no drop off in performance in daily driven street cars. Mostly Rotaries, that are notoriously hot running motors. Hope that helps, Eric Vaillincourt

It was quite hot today, about 37C ambient (99F), driving hard on uphill twisties. Miata is a 2000 with AVO turbo and large i/c. I compared again the temperature at the radiator inlet, and at the heater hose from the back of the head (via the TEC-II temp sensor). The lowest temperature difference while driving hard was about 3 to 4C. With the a/c going I could get the TEC-II to read 108C. I pulled over and let it idle, and the temperature difference widened to 8-10C. When the engine cools down and if driving gently, it looks like the thermostat partially closes and the rad inlet water temp cools down by several degrees, while the TEC shows a constant 94C. So it seems the "short-circuiting" of coolant, bypassing the radiator, is not so bad, at speed. It is pretty bad while idling (low coolant speeds), which probably explains why so many M2's overheat in stop and go traffic. I also tested the Spal 11" fan in my SO's stock 2000, which replaced the aux fan. It seems it has helped. Previously while idling with the a/c on, and I disconnect the main fan while leaving the aux fan running, it would overheat quickly. With only the Spal running, it took quite a long time for the temp needle to start moving to the right. The Spal for my turbo Miata is on the way. When I have it in and I test it I'll report back.

.. I found that water entering the rad was several degrees cooler than at the back of the head. More so when idling. The theory is that some coolant short-circuits the rad. Jason Cuadra

The Analog Devices part # AD594 and AD595 is a thermocouple conversion IC. It can be directly connected to a thermocouple, and output a useful voltage range for measuring applications. It is a single chip solution that can be run off of a single supply voltage. With a few external resistors, the gain of the output can be tailor fit to most applications. I plan to build a circuit to adapt K-type thermocouple output to the Bipes ACU for temperature monitoring of the post supercharger air stream. It probably won't happen any time soon, but I thought that any of you that may have the ability to design such an interface should have this information. The application note for this device spells out the formula for adjusting the output gain to your desired level.

Steve Kiffmeyer

If someone does plan to do this, make sure that you bring actual chromel and alumel wires (not copper leads) all the way to the chip, and use proper connectors with contacts made of chromel and alumel also. Doing this will allow +/-1.5% accuracy with the A-grade parts or 0.75% with the C-grade parts. 1.5% is +/- 15 deg C under boost, so you don't want any more error than that. The cheapest versions of the chips are over $15 ea and the better grade chips are around $45 IIRC, and those connectors are pricey too, which is part of why thermocouple amps are so expensive

Ray

"I have an EGT probe mounted in the downpipe (after the turbos) of my 3rd gen RX-7. It's nearly useless as the needle moves around very slowly, completely missing out on any short temp temp spikes that I know happen at redline at full boost. Almost useless for tuning, IMHO. OTOH, in my turbo Subaru, I have the probe mounted in the exhaust manifold just a few inches away from the exhaust valve to cylinder #4. Mounted there, temp changes are nearly instantaneous with relatively huge temp anges. It also catches temp spikes with excellent repeatability. In fact, I can even catch the temp readings dropping a bit during the 1/2 second between WOT and when the boost comes on hard. Both are autometer EGT gauges." Shiv Patak

"My Autometer Ultra-lite series 0-1600f EGT has a separate signal amplifier box. Actually, the thermocouple and amp were purchased independent of the gauge, so it may be feasible to use them as input for the FMECU. I think that it is only the newest, street-series, gauges that don't have the amp." Jeremy L. Schuster

After having lived with just one EGT probe (~3"down in #4) and having seen some OEM testing (discussed previously) I am considering adding another probe at the turbine inlet. IMO, you need to know _two_ temperatures- exhaust port outlet and turbine inlet. Recall that the testing I observed showed the collector as 80-100*C _hotter_ than the port mouth at WOT. Given the rich mixtures that we run it's quite easy to surmise that our systems would be similar because of continuing combustion in the exhaust stream. Robert Mangas

..i.e. inaccuracy of using surface mounted thermocouple; I don't know what that would look like. Cherry red (1100 + F) is clearly available on the outside of the manifold. While doing so, the gasses are usually around 1400 F. Guess then, that an error of about 300 would be reasonable. Corky

NA MR2 would cruise at about 1000+ and under accel it would see 1200 routinely. 1400 was too hot.

Exhaust temp gauges .. Autometer?

O2 –Lambda probes

It really is tough to tell much from the four wire at high boost. If you are really rich, it'll drown the sensor and keep asking for more fuel. Take a look in MLL at your fuel curves in the 3d plot. The shape of the four,five,six hundred rows should all mirror each other, just at higher levels as the boost goes up. Bill Cardell

The OEM O2 sensor will usually work briefly under boost, before it gets hot. Try logging a run up to 5500-6K at very low MAP (60-70) and then bring on full boost. The O2 data should be pretty good for a second or two of boost, although all AFs of less than a certain level all look the same (See exhaust gas plot on FM website). Also check to see if your injDC is getting over 2000. Ray

A/F ratio was right on the money. (well a tad high) 12.75:1 with a temp compensated wide-band O2. That's really lean compared to what I run. I routinely get into the mid to high 11:1 for moderately boosted street cars. This is assuming our widebands are similarly calibrated, of course. my 2c, shiv

The NTK sensor to be used is from a Honda Civic VX, 1992-1995, #36531-P07-003 It is a five-wire sensor. You can get the sensor from http://www.thepartsbin.com when they have them in stock. The part number is Part #: C5010-75044 Brand: BOS Product: Oxygen Sensor OE connector Honda Civic 1.5 VX 3Dr 1992 It comes in a Bosh box, but is an NTK sensor.

Total cost was about $160.00 including the sensor. Not too shabby. One of the other fellows that built this same circuit and used the Honda sensor also has a $8k Horiba lab grade unit and the DIY unit was within 1-2 percent of the Horiba from 10:1 down to 18:1 side by side. Price on the sensor can vary from as little as $120.00 to almost $200. Jess Gypin

I'm currently datalogging an FJO wb unit (which I expect is comparable) along side the OEM O2 sensor. What I'm seeing confirms that under steady-state conditions the OEM O2 sensor output falls as it heats up (as we've all read). What I'm also seeing is that the response of the wb is much slower than for the OEM sensor. FJO has confirmed that the basic sensor (not the electronics feedback control loop bandwidth) response to a step change in A/F is about 1/3 of a second for the sensor output to move 50% of the change. IOW the sensor reading is approximately the average of the A/F for the previous one whole second (do the math). That slow a response makes dyno tuning difficult and also makes the wb unsuitable for L3 control in the NA area where the OEM sensor does work well. I wonder what's different about the Honda OEM setup, other than that it's wideband area is only on the lean side of stoich. Ray

FM2 turbo clamps required

Intercooler clamp group

Throttle body clamps 2.5 inch 2 ea.

Intercooler out 2.25 inch 1 ea.

Tubes to intercooler 2.25 inch 13 ea.

Inlet and Surge Valve Group

Turbo end of hose 2.50 inch 1 ea.

Onto hose end 2.25 inch 1 ea.

Surge Valve 1.375 inch 2 ea.

So it looks like 15 2.25 inch clamps and 3 2.5 inch clamps for all of the piping and inlet and outlet connections, then 2 1.375 clamps for the BOV.

Kurt at PBC is doing kits – Aeromax is $75/kit

1.6 Desktop Dyno settings; Bore: 77.98mm (auto calculated) Stroke: 83.57mm (auto calculated) 4 valve head w/ stock ports Intake valve 29.32mm Exh valve 24.49mm CR 9.50:1 300 CFM / 1.5 inHG Manifold - Sequential Fire Inj Stock exhaust Cam "High Performance Street" Hydraulic lifters Intake 6.74mm lift, 278 deg duration (seat to seat) Exh 6.41 lift 278 deg duration (seat to seat) Overlap 134 degrees. Brad Franks

True, a stock SR20DET power level can be duplicated with turbo kits on a BP, but what if someone wanted "reliable" 450 hp instead of a "reliable" 350 hp? Put another way, I can put 22 psi into a Miata BP and get 350 hp or I can put 15 psi into a 2.3L version of a FE3 and get 350 hp and have it last far longer.

There is no currently available and inexpensive stroke kit available for the Miata 'B' engine. Sure, an offset ground crank can be done but that has it's own issues. A simple +2mm overbore gets the BP to 1922cc but the max the block can support is an 88mm crank using the same rods (rod ratio) and then the block can be overbored +2 .. maybe +3 and be reliable (86x88 = 2044cc).

The displacement and block is not the only comparison factor though as valve size and head ports play just as important. The BP valve size is sized for about 1800-1900cc for about 7000 rpm. More displacement makes the valve sized smallish.

A FE3, by nature of it being physically larger, can support a 94 mm stroke (available from the factory as the F2 crank) and as much as a +5mm bore (91x94 = 2445cc). The crank, rods, piston wrist pins are all beefier by 20-30% so it is designed for the extra displacement and power levels. The valves (+3mm over the BP) and ports are larger for the extra air needed for the extra displacement.

Randy

the genuine Mazda FE3 is far superior to the Kia version with better forged parts vs the cast parts of the Kia unit. A good starting foundation would have to be imported and these engines are not being made anymore by Mazda so the supply is limited

Mocal thermostat Mocal or Setrab oil cooler (Earl's is a Mocal, from what I know), I would go with a 19 row or so since you're running a turbo. Mocal block off plate (same as Earl's) -8 or -10 SS braided line For the oil filter, if you want to use a spin off filter, use a Mocal or Peterson mount, but I don't think you can get those with the stock threads. If you want to use a stock type oil filter, use the mount that comes with the Moss kit (it looks like a Permacool). Except, I would ditch the stock filter in favor of a Mobil One M1-108 or M1-105 (big). If you want the ultimate oil filter (expensive too) look at Canton/Mecca canister filters. They have ports on the canister itself, so there is no spin on filter. To change the filter, you change the media. One cartridge runs about $12, so it's even more expensive than changing Mobil One filters. However, the Canton/Mecca canister filter will flow as much as 2 Fram PH8 (big Ford filters), and it has no bypass valve, so you're always filtering the oil. I believe it filters down to 8 microns as well. You can find Mocal and Canton/Mecca parts at www.pegasusautoracing.com. Setrab can be found at www.bakerprecision.com Other vendors to check out would be: www.truechoice.com www.racerpartswholesale.com I am currently running the Moss kit on my '99 (which I believe is a 13 row Mocal, but no thermostat), but I plan to replumb it with SS braided hose, Mocal thermostat, and a different mount so that I can use the M1-105 filter. William Howell

The best way is to look on the castings of the turbo, IIRC the compressor should have a .60 A/R and turbine a .64 A/R if it is indeed a large BB. - Beau

If it's a T25 (which it sounds like it might be??), then you're SOL AFAIK. If it's a regular T28 then the compressor is a T3. T3 maps are all over the web, like here: http://turbofast.com.au/FlowT3.html or here http://www.turboneticsinc.com/comp_maps/fig1.html. I don't know what wheel it is though, so you'd likely have to measure it and compare to the specs found here: http://www.turboneticsinc.com/catalog/comp_wheels.html.

Jeremy L. Schuster

T3/to4E on cast manifold is Porkee that BC at FM is playing with – did 300rwhp uncorrected

T28 turbos; T25 turbine + T3 compressor = T28.

T28 means a t25 exhaust side with a t3 compressor side.

Especially on the majority of turbo Miatas that run smallish T28 turbos at high boost pressures. While they still get gains from each additional PSI, it's pretty marginal. The last few 1.8 FM II I've tuned gained 15-18rwhp when going from 12 to 15psi. Whearas I suspect that my M62 blowered car is still capable of gaining 8-10rwhp from each additional psi of boost (at least at this power level) Even my little non-intercooled M45 gained close to 20rwhp when going from 5 to 7psi. Of course, there are other variables involved such as engine management, ignition system limations, engine breathing/VE characteristics at different mass airflows, etc,. However, if a turbo is sized generously enough so that back pressure is super-low at peak hp, it's possible to see the massive 15hp per 1psi gains that car enjoyed by those running big T3/T04. Downside, as always, is more lag and the need to run big boost in order to maximize efficiency’ Shiv

"The stock ECU is limited in injector size to about a 270-310 cc/min injector depending on how well you want the car to idle. There have been people that have modified the stock FPR to run bigger injectors by lowering the base fuel pressure. The idea behind raising the stock fuel pressure is to get the injectors to flow more fuel. By adding the AFPR or a rising rate fuel pressure regulator is that you can get the injectors to flow more fuel under boost by raising the rail pressure as the boost rises. The problem with the stock ECU is not really the amount of boost, it is that the boost is limited by the amount of fuel the injectors can flow and still let the car idle. If you could get the car to idle with larger injectors than the 270 -310 cc/min, then you could run more boost. Some people have been able to run up to 10-12 psi on 1.8 injectors (230 cc/min) on the 1.6 and the same amount using the 270-310 injectors. It is getting to the edge of practicality as the rail pressures that you must run to support that flow rate are near 110-120 psi and on the edge of leaks and injector lock. I ran 1.8 injectors in a 1.6 at 9-10 psi and 110 psi fuel rail pressures for a time and did not have any issues. The stock ECU has really nothing to do with "reading" the boost pressure at all. The only limitation is how big an injector it can make idle. After the ECO goes open loop at full throttle and under boost, the amount of fuel that flows is regulated by the pressure the AFPR causes in the rail beyond whatever opening and fuel the ECU provides. It is the pressure increase that increases the fuel." Jess Gypin

Your problem is the injector size with the stock ECU. 300 cc injectors cannot be used with the stock ECU. The Stock ECU cannot provide that small a pulse width at idle. See the many threads about this at Miataforum Powermods. 250ish is about the largest you can use and maintain a decent idle O2." Randy

Alternator regulator is inside the stock ECU on later cars Ray

how much authority does the '99 knock sensor have... it can pull up to 5 degrees

the 1.8 injectors are 230 cc/min

"My 1989 626/MX6 shop manual says the 2.2 turbo injectors are 11-15 ohm and 320cc." Randy Shocker

multiply by 11 to go from lbs/hour to cc/minute... fuel injectors"

"At full load the injectors run in batch mode, i.e. they all turn on and off together. At 7K rpm they'd be open for about 15 msec and closed for about 2 msec" Ray Ayala

550cc/min injectors really shouldn't be used in greater-than-300rwhp applications. With a well-sized turbo running 18-20psi on a built 1.9L motor, output should be in the 350-400rwhp range. You'd probably want to go with 720cc/min injectors. Or maybe 650cc/min injectors coupled with ~65psi or so static fuel rail pressures. Shiv

$2261 for basic 4 cyl kit with coils, lots of I/O ports, Canada only really but amazing I/O including 4 PWM outputs (tacho already there) 15 digital out, 8 digital in, 2 thermocouples, 5 analogue in, etc… unknown software (Win 98) but full time data logging.

Link M has the support/programming and it is plug and play pre’96 cars only. $1000

Idle and injectors "There is an ECU solution to it. Upgrade the injector drivers. According to RC Engineering, the minimum, mechanically-limited injector turn on-time for a saturated/high res injectors (or I suppose a low resistance inj. used with ballasts) is somewhere 1.6-1.8ms. Min injector turn-on time for a low impedance injector (without ballasts) is around 0.9-1.2ms. This would suggest that a low resistance injector (with appropriate driver) is capable of delivering ~40% less fuel without binding up. IIRC, the low res. DSM injector are Bosch units and require more juice than their low res. RC/Lucas counterparts. According to Russ Collins at RC Eng., they start to bind at ~2.0ms (vs. ~1.5-1.6 for the more forgiving RCs). Getting rid of the ballasts and upgrading the drivers will give much control of the injectors. Faster ramp up time and lower min on-times." Shiv

"fortunately it's also unnecessary with the RC550's which operate fine at 1.4 msec with resistors in my 1.8 (good idle at 850 rpm)." Ray

TEC-II

"The Vishnu TEC-II kit includes the required sensors, which operate independently of the stock ones (except TPS, for which one wire is tapped for the TEC). In the early TEC-II days when I operated my TEC in standalone mode (removing the stock ECU), among other things I had to figure out the 1.8 fan switching so I used a 1.6 thermostat housing and thermoswitch. Changing the t-stat housing essentially means doing a timing belt job.

Long story short, using the TEC in parallel makes for a much cleaner solution which overall works better than when I used the TEC in standalone mode. I originally used Barry's '1.6 TEC notebook' along with some head-scratching between the two of us (thanks Barry!) to get my 1.8 car running in standalone mode but undid a lot of the changes when converting to parallel mode. AFAIK, my car was the first Miata with a TEC-II running in parallel with the stock ECU. And yes, I put the 1.8 t-stat housing back in. :)

Having BTDT, hindsight, and all that-- I'd have gotten the kit in a heartbeat if it was available at the time. Not only for ease of install and functionality, but price too. I got nickeled and dimed to death with trigger wheel fab, pickup sensor mount, sensor mount fab, and all the other stuff that never gets accounted for... those who want or have TEC-IIs on their Miata don't know how good they have it now. Plus, there is support. When anything went wrong on my car, I had to figure out how to make it better, stronger... myself.

You're right, Glenn, the Link WAS the only plug-in solution available when I originally opted for the TEC-II. I was aware of the Link's plug-in capability and was still willing to undertake the (at the time) daunting TEC install. The advantages of the TEC were that attractive to me.

As for autotuning, not only does the TEC-II have it (with the WinTEC software), but the number of samples to take is user-definable. The TEC's suggested corrections are subsequently highlighted in color on a MAP/RPM/correction table. It's plain to see exactly where it suggested a correction, and how much. Then you can pick and choose which corrections you want to keep." Jay Kavanagh

Doesn't the Haltech "dumb" that data stream down into something it can actually compute in its software? And isn't that a far cry from a hard-wired and dedicated ignition processor that reads every single tooth and void (up to 15k rpm, if necessary). And wouldn't that affect coil charging and spark accuracy when it comes to actually delivering the spark?

The TEC-II does not read off the stock CAS at all. Relies entirely on its 60-2 toothed crank trigger Shiv

I've just installed some large-ish cams in my Linked NA 1.6 254 intake and 260 exhaust, with 35 overlap. The overlap is is not optimal, I'm idling in zones 305 and 310. (50-60 kpa, its pretty funky, all over the place) Sadly, to go along with the reduced idle vacuum, there’s also reduced torque below 4.5k rpm... But she really sings past 5k! Desktop Dyno (thanks to Gary Morrison for doing the calculations and iterations) is suggesting if I put the stock intake cam back in (236 duration) and advance it one tooth, I can make back all the lost low-mid torque, and make gains at the top as well! Seems counter intuitive, even though reducing the overlap (to 31.4*). This is not the best possible option, but its an option available for no money... If its predictions seem to be correct, I may get my intake ground down to the 240 ideal suggested. Fletcher Blades

BTDT - definitely bring the overlap back to 30-32. Desktop dyno 2000 is pretty accurate, it has matched most of my dyno runs. Nothing beats actually trying it though since every motor is a little bit different. I can't begin to tell you how many times I have switched cams (solid too so they need

adjustment each time) and played with overlap and timing to find a setting that I liked. Personally, I would hate to give up the bigger intake cam in order the make the overlap right - otherwise you wasted money on the exhaust cam just to get more overlap. The intake cam profile is what really provides most of the power. I recommend spending a few more dollars and getting an

adjustable cam gear so you can stay with the larger profile cams. -Randy

stock 99 head is worth about 4-5 hp versus the stock pre99 head – Bob Boig testing

Dana, my head guy, suggested that the power came from raising the port floor - GibbP

Raising the port floor; It basically involves making the air change direction less as it travels through the intake port and past the valve. The higher the floor (more vertical the intake port), the more of a direct shot the air charge as to make as it goes past the intake valve. This means more air velocity, less drag and better VE. IIRC, the port floor on the M2 head is a good 3/8" higher than that of the M1. A good analogy would be trying to roll a golf boll down hill and into a hole (at the bottom of the hill). The steeper the hill, the more speed it will carry into the hole. At least that's my take on it. I'm sure I'm leaving stuff out. Shiv

1. Billet ground cams .. custom made from steel bar some 3" in diameter... totally custom. $800/pr

2. Mazda comp cam blanks .. the '99 blanks with no machining on the cam lobes and presumably not heat treated. £560/pr

3. Stock cams reground down with smaller base circle, will be a second heat treat so may be softer. $300/pr if free cams.

The Mazda Comp billets are OEM cams taken off the assembly line before they are machined. Yes, they are unhardened but that is what the grinder will do for you once they are ground to your specs. The only disadvantage I see to the Mazda Comp billets is that you are forced into using the OEM cam timing (or very near to it based on what profile you are using) but I feel that is minor since you can adjust the timing to anything you want with adjustable cam gears. " Randy Shocker

’99 cams A quick measure showed ~.347 ("5A" base circle to apex difference), but they do start pretty quickly Rod Hiorns

"Big cams" are done on the base circle not the lobe tip. There is only about 1mm between the lobe tip and the lifter support. Randy

"Now - there are 46 teeth on the cam pulleys, so that one tooth corresponds to ~15.6 degrees of crankshaft rotation. If the exhaust cam was advanced one tooth the resulting timing (open ~TDC, close ~69 degrees BBDC) would be very close to the 323 spec." Mel Hoagland

"Before easy access to dynos, we tried the exhaust cam adjustment. Obvious change was a less abrupt torque rise in the 4500 rpm range. The change felt to be due to greater torque below 4500. Did not seem to change noticeably at higher speeds." Corky

I'm going to swap the cam pulleys so that the Intake cam alignment pin is set in the E slot, and vise-versa... If you examine the pulleys closely, the I setting is retarded about a third of a tooth from the E setting. So you can change one for 1/3 of a tooth, both for 2/3 of a tooth, or set them normal and jump a whole tooth... that should give adjustment increments of about 2.5 degrees? Fletcher Blades

Does anyone know what tuning changes might result from advancing the exhaust cam one tooth?

"Just guessing from my limited knowledge and playing with Desktop Dyno: Early exhaust opening means more exhaust energy to spin the turbine, yielding quicker spoolup and more boost at lower RPMs. The resulting less valve overlap means less torque at higher RPMs (esp. above 6000 rpms). Peak torque value will be higher, but peak HP may be lower. Peak Torque and Peak HP RPMs will move down. The whole power band will move down in RPM. Your volumetric efficiency curve will fatten at lower RPMs, so for a given boost level you'll have stronger low and midrange torque.

Average power (area under the curve) in the power band might or might not improve. BTW from playing with simulation the average power in the power band is a better indicator of quarter mile time than average torque, and a much better indicator than just the peak power value. (Which happens at only 1 rpm value) You may need more fuel and less advance below 5000 rpm, and less fuel and more advance above 5000." Jason Cuadra

"FWIW: We played around with Desktop Dyno and found that huge ports and really long duration cam found a bunch of power with a low-lift cam. Will be exploring that further." Dan Doehrman

"I found that the stock valve springs were good for about 7800 rpm before they float.

The stock cams and intake manifold also run out of breath at about 8000.

I installed bigger cams and stiffer springs and I have no issues with going to 9000 now. It is my experience that the stock internals can survive 8500-9000 rpm for short durations. EP engines use the stock crank (although heavily lightened and balanced) and they go much higher. If you will be seeing that rpm for any length of time then lightened crank and pistons are definitely on the list. See the dlralt site for pictures of their lightened crank. Mazda Comp sells a high volume oil pump. It was originally designed for the 323GTX so you'd have to get the front of the crank machined a smaller diameter for it to fit. Miq uses this pump and had the machining done on his late crank 1.6.

I run 9000 rpm all the time. No sign of any problem in two tear downs.." Randy Shocker

What valve spring configs are in use with the disappearance of the Crane valves -- is CompuCam still a useful purveyor? I know some folks are using some kind of double-spring arrangement, what parts are actually in use? Sealed Power VS-855 >>> 7) Are the Mazda comp lifters shim-under-bucket type? Yes >>what about 99 OEM? OEM is shim on bucket " Randy

"An Improved Touring racer I know says that it's essential to have the crank chamfered and filleted to prevent starvation at sustained high RPMs on the 1.8BP. Also, I think you might want to begin talking with Dave Lauzier in Canada. I can put you in indirect contact with him (a friend of his who can point you to him). I think I've mentioned this before, but Mr. Lauzier has built a 1.8BP motor for an MX3 that is dynoed at 500hp+ at the wheels before the transmission went ker-blooey. Typically, the 1.8BP can withstand 300-350 on the stock block before it gets aerated." Swervo NOC

"One thing I would do is to replace the main bearing cap with one of Bob's steel ones. This has been a problem in the past on race motors and I would consider it cheap insurance on any buildup!" GibbP

"I called Mazda Comp. to order the proper size replacement bearings for my motor, that they sell a set of "race bearings". I was completely unaware of this. When I asked what made these "race" bearings, the gentleman said that he couldn't read the literature that they had because it was in Japanese, but he could tell me that they are sold as Mazdaspeed bearings and are a better material. The real kicker is the price...$20 per bearing half. So, $40 per complete bearing and $360 for a complete set of rods and mains. Uhhh, damn... I ordered one (complete) rod and main bearing, and got them in on Friday morning. They are indeed made of a different material, and perhaps tri-layer (as opposed to bi-layer for the regular OEM bearings)." bangin'gearz

"I was always under the impression that the 1.8 BP got a steel forged crank starting in 1994 when it had a revision. 1994 also included new design pistons (same dome shape and CR) and rings. Others have said they had info that the steel crank came in 1996 or 1997". –Randy (Dealer wants $500+ for a new)

I just talked to a crankshaft place that had to weld up a bad rod journal on a 99 crank. He said that although the crank was definitely forged steel it was not hardened particularly well. This means that they are susceptible to flat spotting a rod journal if the bearing goes bad (the rod pounding on the journal from the excessive clearance). What this means is that if you hear rod knock immediately stop the motor and don't continue to drive it because likely the crank will be damaged beyond normal undersize repair. The largest rod bearing undersize is .030" and the one he was working on wouldn't clean up even with that much so he was going to weld it back to standard size and then reharden the entire crank. I asked him about the controversy of rehardening a welded crank and he claimed to have done it successfully on many race motors so he wasn't worried. Randy

"In the "must have" pile:

David Vizard's How to Build Horsepower ISBN #0931472245

Vizard is famous for his "Tuning the A-series engine" book(s) where he details how to take a 948cc 36 HP lump and turn it into a 100 hp race motor. Keeping in mind that the A-series engine is a 1930's design. Vizard also has a Chevy V8 oriented pair of books but the Building HP one has most of that info in it.

Carroll Smith has a series of books that are both informational and good reads. These get pretty heavy in the calculation department

"Tune to Win" ISBN #0879380713

"Engineer to Win" ISBN #0879381868

"Prepare to Win" ISBN #0879381434

"Screw to win" ISBN #0879384069

Ok so the last one is really called "the guide to nuts and bolts" or something like that, but ask anyone who knows the series and that's what they call it.

In the "hmmm, I should get some more detail on that" pile:

Ben Watson has a couple of books "How to Build and Modify ....." he covers things like cylinder heads, camshafts and valve trains in one book and intake systems in another. He tends to gloss over the details of actual fabrication, where Vizard's book has diagrams of exactly what a dremel should be removing. But both have good theory and nice pictures. I don't have ISBN's handy (Vizard's and Smith's books are on the shelf next to me)"

Miq Millman miq@teleport.com

"I have A. Graham Bell's "Modern Engine Tuning" and Dalton's "Practical Gas Flow" and I like them very much" Jason Cuadra

Port Work is really well addressed in: How to Build, Modify and Power Tune Cylinder Heads By Peter Burgess and David Gollan Porting, Flowtesting and Procedures by Bill Jones (Good Luck finding this Tome.) Mark Peugeot

Using a ridgid hone is new to me. Hope this will cure my blow-by problems. Procedure I was told: 8-10 strokes with 150 grit and 8-12 strokes with 280-300 grit (for moly rings, Total Seal, and our factory rings. Different for cheaper rings.) followed by 10 strokes with Ultra hone. Bore cleaned between each stone and liberal hone fluid with all. Procedure I used: Went 4 strokes and removed hone to clean and check. Went another 4 strokes. Did this with both stones. Just being real cautious. Would insert and remove with stones retracted. Seems to have far less cross hatch than I'm used to so maybe that's what I've been doing wrong. Followed with 8 strokes of Ultra hone which is a plastic deburring brush. Just a big plastic brush with abrasive inside the plastic. Super easy to use and really made the bore friendly to my hands afterward. A guy told me to get it since it makes the bore friendly to the rings. Whatever that means. Ralph Doehrmann

Oil gauge acting as knock sensor; "At high speeds I couldn't hear the detonation but I could see it on the oil pressure gauge. At lower speeds, where I could hear the detonation, the oil pressure fluctuation *exactly* matched the detonation events." Barry Birdwell

"I have the feeling that the reason for the failures on the #4 cylinders on a dry system are due to using the dry system; the Miata intake is not designed as a wet intake. For those "not in the know" there are two types of intake manifolds, "wet" and "dry". The Miata has a "dry" intake manifold in that it's designed to only flow air into the system. If you think carbureted V-8 you're on the right track for a "wet" manifold, it's designed to deliver both air and fuel through the manifold and into the engine. The inherent design flaw in a dry system is that it's intended to mix the N2O with the incoming air (after the air flow meter) and be swallowed by the engine. Even though N2O is dispensed into the intake as a liquid which soon becomes gaseous the gas still behaves as a liquid while it tries to mix with the air. If the nozzle is too close to the throttle body (i.e. pointing directly as it) the air/ N2O won't be mixed properly before entering the plenum. Most uninformed owners try to place the nitrous nozzle as close to the throttle body as possible to keep their power levels up (part of the power that N2O gives is in the coldness of the intake charge). This usually results in the nozzle being pointed directly at the TB and as such, directly across the plenum and right at the #4 intake runner. Because it acts as a liquid while mixing with the air, and considering that the Miata manifold is not intended to mix liquids, you wind up with #4 being lean and #1 rich. This nets you more Oxygen than fuel to burn in the #4 cylinder, runs it lean, heats it up and then shoots piston fragments through the sides of the block and pieces of the cast aluminum head through your hood.

The proper way to install a nozzle in a dry system would be as far from the TB as possible, but still in front of the AFM (where applicable) and pointing down the length of the intake tract. I'm hoping to see an increase in the longevity of my engine by using the multiport wet system. This way I am dependant only on the stock fuel pump and fuel filter to get the appropriate amounts of gas for the N2O to be properly mixed and into the engine. I'll be running higher HP (NOS claims 80 HP out of the box on the lowest jetting, I'm bargaining for 70)than a dry system in an invariably safer design. If it doesn't blow up on me that is...

;P

This is, of course, complete conjecture. I do not speak with experience, only what feeble amounts of logic my brain has thrown on the issue. For instance, it does nothing to describe why you see fouling on the #4 injector, if anything that would be your cleanest injector." Brad Franks

"I'm installing a NOS Sportsman Fogger system which is a multi-port (one nitrous/fuel injector per cylinder) wet system .. NOS QA really sucks. I spent about 4 minutes with a dental pick cleaning out all of the polishing compound from the thread holes on the junction blocks. The least they could have done was soak them in lighter fluid for a few minutes before packing them up. NOS QA sucks (again). I found quite a number of small metal barbs and shavings throughout the bits and pieces as I pulled them from their blister packages. Yes, that's right, they ship everything by laying it out on cardboard and heat shrink wrapping it. I don't really know what I was expecting, but for a product from a manufacturer known around the world, I was expecting something more than being shipped like it belongs in a Toys -R- Us end cap. Did I mention that NOS QA sucks? Yes, against the suggestion of Scott, I ordered the "chrome" version of the kit which included polished junction blocks, polished SS lines, polished runners and polished solenoids. Even thought he majority of the system is invisible once installed, it just seemed more appropriate to install the "cleaner" looking package to make maintenance easier (it's easier to find dirt on a shiny part...). well, most of it came polished but 4 of the 8 runners were dark steel while the other 4 where well polished." Brad Franks

HIGHPOWER SYSTEMS, RANDS LANE, ARMTHORPE, DONCASTER, SOUTH YORKSHIRE,

ENGLAND, DN3 3ER, UK.

TEL +44 (-0)1302 834343

FAX +44 (-0)1302 833969

start at 25hp

maximister is NOx Powermax at £389

minimax basic start 50% go to 100% £150

Ecoblaster 100i comes with 5 lbs bottles in either size

costs £48 to upgrade to 11lbs bottle full of gas

0-1500 psi in hot countries

7-900 psi in UK

bottles tested to 3 times operating pressure

Have bike ignitions with lost spark but analogue only .. now have US Dyna-coils with digital programmable but needs trigger...

Progressive on throttle control is now here .. done one VR6 but it interfered with ECU signal so have reduced the signal loss/draw .. FOC to be a test car :-0

5lbs long = 4"Dx20L+3" valve

5lbs short = 4.5"x15L+3" valve

11lbs = 6"D+23L+3" valve

Trev the boss .. spoke to him

NOx express bottles;

5lbs 16.5"x5.25"D

10lbs 19"x7D

15lbs 25.5"x7D

20lbs 25.75"x8"D

"Exhaust size ..the real test is back pressure. Put a pressure gauge in the tailpipe ahead of the converter and read the total back pressure. Okay starts at 3.0 psi, and good is under 1. Read only at max boost and the redline, naturally." Corky Bell

"Copper plated steel nuts. Used them throughout the installation and haven't had a single one come loose in over the year they've been on for. Basically they're a correct size nut which is then given a relatively thick coating of copper. The copper conforms to the thread as you put them on acting as a locking agent. Downside is they're expensive (~$2 a nut) and a use once item. If you take them off throw them away and replace with new." Matt Apilson

"Dropping the CR will remove about 30 F per point, when working around the 8's and 9's. At the same knock margin, by raising the boost to put that amount of heat back into the charge would be equivalent to about 4 psi per CR point. The boost should be worth 13/14% in power, while the lower CR will cost about 3 to 4% of that gain." Corky Bell

"Hmm, assuming a stroke of 80 mm, and 6000 rpm: piston motion is: x(t) = 40 * sin(2pi * 100 *t) * mm this assumes an infinitely long connecting rod. The motion is a bit more complicated for a Miata connecting rod :-)

Velocity is the derivative: v(t) = 8*pi* sin( 200pi * t) * m/sec

or a peak velocity of around 55mph.

Acceleration is the derivative of velocity: a(t) = -1.6 * pi^2 * km * sin( 200pi *t )

or a peak acceleration of 1600 g's.

So for every 100 grams that a piston weighs, that's 355 lbs of force. And that goes up with the square of RPM - 10% more RPM is 21% more force on the conrods." Jason Cuadra

One of the pistons came up .027 over the deck! I found the problem was that the stock rods varied by .008" between them. In my case I milled the pistons so they are all an even .012" over the deck, giving me a squish of .030-.035 depending on how much a 1.6" stock head gasket actually

squishes....Gary & Hakuna

I -zero decked my block to be even with the compression height of the new pistons on my 1.8 - hence the gasket thickness is my piston/head clearance - good since the gasket for the 1.8 is thinner - I think i the .028" - .032" range .Stan Whitney

1mm overbore it's not really a 1.8 = (83x85 = 1839cc). 84x85= 1884cc

Engine failures ; #4 cooks if you have a cooling system problem. #1 cooks if you have a mixture problem.

"Gude Performance (Bullfrog).. bad delivery, promises, performance.. bad experience.." Russell

"GT-2 lists the Ford Probe with the Mazda FE 2.0 engine is legal with the Cosworth YAC cylinder head!!?!!? I wasn't aware any Cosworth heads fit Mazda blocks.

Mazda Comp has extra beefy main caps for sale for the 'B' engines and are part 0000-01-5210, they are $242/ea

Cosworth makes many engines. The YAC is loosely based on the 2.0 liter OHC Pinto and FF2000 engine. It is DOHC and has 1994cc with a 90.82 bore and 77mm stroke. There are no cars sold in the US with the YAC engine but it is used in SCCA racing in Sports 2000 and, I believe, in FC racing. In Europe it is offered at about 180-200HP in street NA trim in various Ford and tuner cars. Apparently the Mazda 'F' series of engines has more in common with Ford than first thought" Randy Stocker

"as far as I'm aware GTX rods, well the BP ones at least, are shot peened but I dunno if that’s relevant as for all I know the mx5 rods are shot peened too! Although the GTR BP rods are definitely wider for increased strength, according to mazda BP manual which list the widths as 18mm/22mm and 21mm/27mm for GTX/GTR respectively. the GTR rods also have white paint marks apparently. The GTR BP motor also uses sodium filled valves and (according to some sources) hollow camshafts" Rick Morris http://www.ozemail.com.au/~kevmo/

"Install the AFPR after the stock one in the return line to the tank. People have had trouble when the stock FPR went bad so I would assume removing it might give you trouble too." Larry Alster

Here is a formula for calculating the length, opening to valve seat, of a single intake runner per cylinder.

L = 1100S / N

N = rpm in the middle of the power range

S = the no. of crank * ABDT when the intake valve closes

By following the examples it seems that the stock runners are the correct length for getting torque peak where it is. Measuring from top of the valves to outlet in the plenum I see about 14". The examples also point out that for a 1.6 25 square cm is best runner size for torque at 5500 rpm and 29 square cm is best for torque at 7000 rpm. The stock intake manifold shows about 4cm X 2.5cm so there could be some gains (?) by opening up the port size.

WRC rally cars - in some quotes about the ford focus 2.0l turbo engine - they claim to be using substantially more than the stock 10.6:1(ouch!), w/water injection. For about 300+ hp, and 400 ft/bs of torque - through a 34mm inlet restrictor!

1) We have successfully tested our valves to 60psi.

2) As far as flow is concerned, we know that our valves will work perfectly on a 2000cc engine with a large Garrett T04E turbo running 2.1 bar boost. We have not found a 4 cylinder engine yet that requires two valves to stop compressor stall.

3) We are unaware of any heat related problems with our valve, but common sense tells you to mount it as close to the throttle butterfly as possible or as a bare minimum after the intercooler away from the massive heat of the turbocharger.

4) Both inlet and outlet are 25mm.

5) The main body is 56mm diameter

6) The valve is approx. 78mm from the bottom of the 25mm spout to the top of the unit where a plastic adapter screws in to allow fitment of the boost/vacuum pipe (recommend 3mm silicone hose).

As mentioned on the 'phone, we also produce a 32mm to 25mm alloy 45degree reducer that retails for £8.50+VAT. 25mm silicone hose (red, blue or black) always held in stock.

Bruce Hatton BAILEY MOTORSPORT

"WRX STI Models

These cars quoted power output of 280 PS (276 BHP) is whilst running on 100 RON petrol. In the UK we can only get at best 98 RON SUL (super unleaded ..my "4 star"). Normal UL (unleaded ..my "2 star") is 95 RON. I have seen graphs for an STI running on UL which indicate the car achieved around 254 BHP. The same car then had a subsequent run done on another day but using SUL and managed to achieve 276 BHP. These power runs cannot be directly compared because of the time difference between them but they give you some idea of the difference between SUL and UL in an STI." .. off web somewhere!

"head work depending on what you do can be anywhere from -5% (if done poorly) to 15% of your output."

Talked to Peter Fisher of SP Performance, Orchard house, 2290 Stratford Road, Hockley Heath, Solihull, West Midlands, B94 6NY Parcelforce code R729999A tel 01564 782531.

"8 valve engines eg Golf GTI, 20 bhp increase for straight head work £300, fully modified head, new cams & lifters 180 bhp £850."16v engines eg Elise, no problem 100 bhp/litre 160 bhp MX5, £400. Full race spec 240 bhp, £1950

Gas flow/port 550 GBP vat

Gas flow/port with bigger inlet valves 1000 GBP (Clubman spec) .. should be 1700

... very interesting chat with him for 30 minutes (don't know how he makes money if he spends all the time on the 'phone .. he did ask if I was calling after the article ... must get 10 a day!!), He is into high flow at low vacuum levels which occur at low rpm and also every stroke at TDC ... good idea. His heads are winning heaps of stuff at the moment (according to him :-) ) with a figure of 300 hp from 14.5psi boost seen as easy stuff.... he guessed at me making 180 hp at the moment (cw 210 rwhp on a particular Sun rolling road). 4 weeks delivery in real time (i.e. not 'lets be silly and unrealistic')

’99 head when reworked gave 14% flow improvement. Cost for next stage; extra 2mm of head diameter gives 10-12% more flow and 250GBP for seat inserts, 250GBP for valves, maybe 160GBP for springs.

Cams cost 550GBP for a billet grind set from Kent Cams, 200 GBP for grind if blanks used. Total cost of fully done head is 3000 GBP plus VAT on all prices.

BTW ... 1.8 Exhaust valves are 28x6x102, non sodium filled with type 3 cotter heads (single slot) FAI part number EV4322, Inlet IV4321 ... me looking for sodium filled exhaust valves .. but 6mm stem is too small for BMW/Mercedes/VW.

Headwork is going to improve the systems volumetric efficiency. This will, all other things equal, raise your peak and average cylinder pressures. It will also cause you run run leaner since mass airflow has increased with no change in MAP readings. To compensate, you'll probably have to add more fuel and just maybe retard a degree or two of timing at full boost. This is assuming, of course, nothing else has changed in your system. my 2c, Shiv

Below 3500 rpm there were no gains, but by 4000 they were significant and from there on I have got an average 10 to 15 bhp gain. Peak power has gone from 223 rwhp to 247 rwhp near 7000 rpm. All in all a good gain for some conservative headwork. Steve Willington. 1.6L FM2.5 @ 15 psi

"I am entertaining a 3-angle grind on intake valves only so the contact area of the exhaust valves isn’t reduced and cause them to get hot … was showing me how they made a slight hourglass shape beneath the valve seat for a venturi effect. " Ralph Doehrman doehrman@soli.inav.net

10 inches is a NA standard, it may or may not apply to boosted apps. Flow characteristics can change dramatically when boost enters the equation. Ask for numbers at 28 inches when you have or are contemplating boost

Flow Quick Unit $595

Flow Quick Software $99

Wood $50

PVC Piping & fittings $30

6.25 HP shop vac from Sears $130

Total flow bench cost: $904

Repeatability < 1% with test tube... (about .5% average)

True Accuracy < 5% (unknown until I get a reference flow from a superflow.)

Range 0-450 CFM @ corrected 28" vacuum.

1.6 head after porting (Gary Morrison) 10 inches of water

Intake

.100 30.6

.200 69.6

.300 95.3

.400 107.2

.450 113.2

.500 115.24

Flow numbers.

These are all 1.6 intake numbers. The first set is stock. Second is with general cleaning up of the intake port. Third set is after unshrouding the intake valves inside the combustion chamber. We tested it twice and the number were the same. We are now wondering if the stock numbers are correct at low lift.

Tom says that .200 is a good place to have good flow and that unshrouding the valves appears to do more good than cleaning up the intake runners. I'm shopping for a set of valve seat cutters so if anyone knows where I can get them please let me know.

Lift Stock Mild work Unshrouded

.050 22.1 17.6 18.4

.100 43.0 39.2 41.6

.150 64.0 60.5 64.5

.200 79.5 77.4 82.0

.250 91.4 90.4 92.0

.300 99.0 99.2 100.5

.350 103.0 105.0 107.0

.400 105.5 109.0 109.0

.450 106.0 111.0 111.0

.500 105.5 111.0 112.0

.550 105.5 111.0 111.0

.600 105.5 111.0 111.0

By Dan Doehrman

Dana at http://www.intekra.com/ims has Gibb’s head

Stock 1.6 head Measurements are at 10" using #2 cylinder. Head had been cleaned but is not modified.. Flowmaster bench. .. extra numbers are modified 1.6 by Fletcher Blades

>Intake

>.050 22.1

>.100 43 30.52

>.150 64

>.200 79.5 69.98

>.250 91.4

>.300 99 94.73

>.350 103

>.400 105.5 106.37

>.450 106.0 112.9

>.500 105.5 115.08

>.550 105.5

>.600 105.5

>

>Exhaust

>.050 17.5

>.100 33.2 10.8

>.150 49

>.200 65 45.81

>.250 74

>.300 82 72.52

>.350 85.5

>.400 87 87.7

>.450 88 92.0

>.500 89 94.23

>.550 89

>.600 89 Ralph

Flow numbers on a 1.6 head at 28" from Dana Johnson at Import Machine Service.

Lift Stock Intake Ported Intake

.050 36.9 41.2

.100 67.8 76.0

.200 129.1 140.4

.250 146.4 161.8

.300 159.7 178.8

.350 166.0 189.0

.400 169.5 193.4

.450 172.0 197.7

.500 174.0 202.0

Lift Stock Exhaust Ported Exhaust

.050 34.7 37.4

.100 63.7 70.2

.200 118.5 123.2

.250 135.6 148.6

.300 147.7 165.8

.350 151.3 173.3

.400 154.3 178.4

.450 155.4 182.0

.500 156.6 184.4

Les. www.apexautoeng.com

"My '99 1.8 head chamber volume was around 57cc - crudely measured by covering and filling with a syringe." Stan Whitley

I phoned Terry at AVO and he said the "shoulder" of the combustion chamber could be reduced slightly, and the combustion chamber made a little more "bowl-shaped". He says it's very effective on Skylines and Mitsus running hi boost and he can run significantly more timing and gets more power. What might this do on a Miata's swirl and squish? Jason Cuadra

Coatings

"Painted the turbo, manifold, and down pipe before the install a year ago. Spray can of... "VHT hi-temp Nu-Cast manifold coating SP-998 Cast Iron" A few dollars down at the local auto parts store. Good for 1500 F, 815 C. (if you apply it correctly... cook it) It has flaked off of my down pipe in a few places, which I touched up, but the manifold and turbo look good. No rust". Mark S. Allen.

There are two similar things .. pre-combustion and pinging/pinking/knocking/detonation.

.. the easy one to understand is pre-combustion .. which leads you on to understand pinging..

The engine sucks in some air/fuel mixture .. if you could keep on compressing it .. it would eventually self ignite and explode .. this is pre-combustion as it happens without a spark .. it is how diesels run .. and when cars 'run on' after the ignition is turned off .. this is what is happening .. the hot carbon deposits are self igniting the fuel..

.. this leads onto pinging... slightly more complex. In the normal cycle .. the engine sucks in air/fuel, compresses it, explodes/expands it and finally ejects it only to suck some more in.. the point we are interested in is the compress/explodes bit .. the engine compresses it and at some point the spark plugs explode/set fire to the mixture .. trouble is that the fire does not instantly burn the mixture but takes time .. and so the spark actually occurs before TDC or maximum compression so that more energy/power can be extracted from the engine.. the trouble is that if the spark occurs too early it causes the mixture to get too hot .. and so try and expand ... but the engine is compressing it still .. so the pressure goes up .. now in the edges of the combustion chamber the pressure has risen so much that the fuel self ignites (remember pre-combustion) .. these self igniting pockets create pressure waves .. which meet somewhere near the middle of the combustion chamber ..here they

add to each other resulting in pressures some 40% larger .. and temperatures up to 18,000F (first number is guess.. second from Corky Bell's book Maximum Boost) .. the engine cannot survive these for very long so bits start to melt .. normally the piston tops.

http://www.autospeed.com/A_0353/P_1/article.html DIY knock detector with headphones

Intercooler losses

"Let's assume the ambient temp is 80 F. This is 460 + 80 = 540 R. Further suppose the compressor raises the air temperature by 150 F to a absolute 690 R. If we stick an 80 percent efficient intercooler in, we'll get rid of 0.8 x 150 = 120 F of that temperature increase leaving a 150-120 = 30 F increase. This is 540 + 30 = 570 R. So the density of the manifold air goes up (690/570) - 1 = 21%. We would expect roughly this increase in power.

However, in this 80 percent intercooler, we'll lose 1.5 psi. So 14.7 + 4.5 = 19.2 and 14.7 + 6 psi = 20.7 psia. 1 - (19.2/20.7) = 7%. So you lose 7% of the air for flow losses. So the net increase is 21 - 7 = 14 percent increase.

This is a case of just sticking an intercooler in a system, all other things being equal. In actual practice the wastegate control signal usually comes from the manifold after the intercooler. The wastegate makes up the manifold pressure loss, at the expense of a little more back pressure on the turbine side....so you don't get your full 21 percent....unless you turn the boost up a little.....and if you do that, you might as well crank it up until you get the same manifold temperature you had before....at which point you have about 35 psi.....

Aren't turbos fun?" Lance Karl Schall

BEGI System IV intercooler to a FM2 Racer Intercooler; The difference in efficiency is only about 3%. The need for a large core is to keep the internal pressure losses to a minimum.

http://www.laminova.se/ have a patented water/air intercooler

Simon Knapton’s Supercharger water/air intercooler was by Pace Technology. Norfolk. http://www.paceproducts.co.uk

air temp inside the turbo compressor itself; On a 90F day, it would be approximately 225F at 12 psi Corky

"Some of the DSM's (2.0 l, 12-16psi)run quite well with 3" exhausts - but you give up a little off boost

power. The norm is 2.5" for up to 350hp for those guys. It's also tougher to keep a 3" quiet ;)" Stan Whitney

my 'low-boost' idea;

.. to allow me to do my 'no-brains' foot to the floor through the twisties .. or wet dark late nights.

Idea being that you fit an oversized wastegate diaphragm/actuator to allow 2-3 psi to lift the wastegate but maintain spring pressure so wastegate seat still has enough force on it at 14-19 psi.

My 1.8 FM2 has a 2.5" diameter actuator with about a 0.75" stroke. It lifts at 9-10 psi currently.

So .. 2.5" & 10 psi gives a spring load of 49 lbs .. rate unknown .. I want to run 2-3 psi when the boost control solenoid is disabled .... room for a 5" or less diameter actuator so I'll stick with that .. this

gives 3 psi which is just fine.

.. additional detail would be fitting a 0.5 bar check valve to atmosphere so that actuator could not over pull the wastegate and fitting a 49 lbs at fit point spring. Not sure if spring fitted load is affected by wastegate area

and back pressure as with a back pressure ratio of 3 (wild guess) and 19 psi that is 57 psi on the wastegate area .. surely the spring needs to be able to hold this.

So ... would the Link control boost from 3 psi to 19 psi ?

.. are there stock 5" actuators out there which are 35 psi or so rated (you could used an air brake actuator off a lorry but they are heavy and rated to 150 psi) .. I do have someone in the UK who would make a custom actuator ..but first what holes in my theory? Malcolm G-S "Dump the poppet style altogether and go to a ring sealed butterfly plate valve" Lance

Ram air is fun. Try calculating the pressure rise:

P = density x velocity squared / 2 x gravity

where density = .072 lb/cubic foot and gravity = 32.2 ft/sec/sec

Corky

so, if I'm correct, one would have to do 61mph to have a 0.1psi gain..

http://www.ramairmakes.itgo.com/

FM exhaust manifold studs (to convert outer 4 to studs not cap screws);

60mm long with 15mm and 20mm threads at ends in M10 x 1.25.

This is copied off the OEM studs and compensates for the difference in thickness between the top parts of the manifold .. for a 1.8 anyway. But it does not let you fit the studs after the manifold so are too short.. really you need them about 75mm long with 15mm and 45mm threads so you can fit them after the manifold.

Boost control on Link; using 1/4" fuel hose for the signal lines to and from the solenoid and using a Fram #CG3388 fuel filter on the exhaust port of the solenoid for a restriction. Remove the spring and plunger and glue it on to the exhaust port with some silicon sealant.

FM3 gaiter for inlet pipe to airbox baffle;

A visit to my friendly neighborhood Johnson/Evinrude dealer got me the part number for the boot I used to seal the compressor inlet pipe to the FM III airbox baffle: Seachoice ( brand ), control cable boot, #29251. Should be available in any marine store for ~$10. Just trim off the excess bellows to attain a snug fit 'round the compressor inlet pipe, then screw/rivet the boot to the baffle ( four holes are pre-drilled in the boot). If you don't want to drill your baffle, the boot seems to fit plenty snug against the inside wall of the baffle, if positioned properly. Glenn Buononato's

The new software does not begin listening until 3000 RPM.

The old units will be set to 10° knock control range. The new blue units still allow you to select 10/20

Switch 2 is still the retard all/retard separate select.

Switches 3 and 4 select 4°, 6°, 8°, or 10° of RPM retard.

RPM retard begins at 3250 RPM and is all in by 4250 RPM.

RPM retard is gradually turned on by the Mass Air Sensor. High RPM and low air flow will not cause any RPM retard.

Please specify 1.6L or 1.8L and be sure to include your return shipping address. No P.O. Boxes please. Include a check for $35.00. This covers programming and return UPS Ground shipping. Include ten dollars extra for

2nd day air and twenty dollars extra for next day air. Please allow two days processing time.

J&S Electronics, Inc., 13925 Parkway Dr., Garden Grove, CA 92843 www.safeguard.bizland.com

"The technique is to choose a few zones to concentrate on in rows 4 through 6. Add timing until the link pulls it back down, then add fuel in the zones that have been pulled, until the power begins to drop off, then go back to the previous setting. Then go on to the next ones of interest. Remember - the Link interpolates between zones, so even if you're not running up to 15 psi, row 6 will have an important effect on the overall power." Mel Hoagland

"Before changing out my fuel filter (car has 12k miles) I measured the fuel system flow vs. pressure characteristic. This was to see if a hi flow pump was justified. I took out the little piece of plastic fuel hose that connects to the fuel pulse damper (which then goes to the fuel rail). I attached a 6 foot length of fuel hose. On the end of it I placed a tee. One end of the tee went to a fuel pressure gauge, the other to an adjustable spigot(?), which then went to a short hose which emptied into a pan or a bottle, whichever I wanted. I jumpered the fuel pump node in the diagnostic connector, so the fuel pump would remain on when the key was on even though the engine wasn't running. With the pump going, I adjusted the spigot (and resulting flow) to get my desired fuel pressure (the greater the flow the lower the pressure). I timed how long it would take to fill a 0.75 liter bottle (it varied from 25 to 42 seconds). I did this for max pressure, and 5 psi increments down to 30 psi. Here are the results: pressure flow(L/min) flow(lb/hr) 30 1.8 171 40 1.5 143 45 1.45 138 50 1.25 119 55 1.18 113 57.5 1.07 102 60 0 0 Notice that fuel pressure at 0 flow is 60 psi. Notice that fuel pressure stays relatively constant to only about 1.1 liters/min or about 105 lbs/hr. Above that flow rate the pressure begins to droop. Note that this test was done at ~12 V system voltage. When the alternator is running system voltage is typically 14.5V. That's about a 20% increase, which will increase flow by 20%. I estimate my car is drawing about 150 lb/hr at full power. My fuel pressure must be dropping to 35 psi or so. Not good. I should have mounted a fuel pressure gauge. I don't know of anyone who has on the M2, to report if the fuel pump is up to snuff. After replacing the fuel filter (pain in the ass because I parked the car with the fuel pump side against the wall, plus I didn't back it onto ramps so I had little space, and fuel dribbles down your arm - that's another story), I remeasured a few points in the characteristic - no discernible change. Oh well. I'll get that Walbro in, and a fuel pressure gauge. " Jason Cuadra

Is there a stud girdle available for the bottom end? Not that I know of. 2) Are there any stronger crank bearings/caps available? FM has a steel center cap replacement.

What is the MAX that the piston can protrude from the block? This is for a 1.8 Motor

"Nothing. They should be zero deck or .002 in the hole if an overbore is done." Randy

"I recently built the following motor and here are my results; I used Wiseco 9:1 pistons, .050" gasket, balanced the motor, knife edged the crank and ceramic coated the piston tops. The cylinder head was completely untouched and the motor had a 1mm overbore. 8.8:1 compression vs 9.5:1 compression stock. The motor appears to be VERY detonation resistant but more interesting is the results when compared to the stock '99 motor. Comparing the dyno with my stock '99 motor was rather interesting. Same programming on both motors. Same Turbo System on both motors and same Intake on both motor. Exhaust on the new motor was a Magnaflow 2.5" system and the stock '99 was a 3" open pipe. Boost levels were as follows. new motor 9 PSI, old motor 16 PSI. Now most of you would figure that with 7 PSI more boost that things would be in favor of old motor with a 3" dump, or at least I would, despite the .040" overbore (2 Cubic Inches.) I am here to tell you that the motors made nearly the SAME level of power. At 5500 RPM both motors made apx 212 HP to the wheels!!! Whatever I did (thankfully I documented the build) obviously worked REALLY well. Remember NO Headwork. The dyno graph on power looks like a 45 degree angle and the motor is extremely strong... All Numbers are UNCORRECTED. My guess is that this motor could come close to 270 Uncorrected HP with only 10 PSI of boost. This is with a 99 Piggyback (Yes the computer I love to hate.)" Mark P

"I can second the spark advance/knock resistance on my '99 head, Even though the dyno shows 30-32 degrees total for best power, I was running up to 45 degrees with no hint of knock (@ 11.6:1 on 96-98 octane!)" Stan Whitney

Pre-theft, the car dyno'd, in stock form, at 114rwhp. With BSP headers, intake and TEC-II, it dyno'd at 132rhwp. With the addition of a 5psi JR SC and 550cc injectors, it dyno'd at 178rwhp. With the 7psi pulley upgrade, it dyno'd at 196rwhp. Then it was stolen, abused, stripped and recovered. Since then, the car was was put back together as above, with the exception of a prototype M62-based JR SC kit, a big fatty custom-made air/air intercooler, JR Headers and JR cat-back exhaust. Today, at 9psi, it baseline dyno'd at 218rwhp @ 6600rpm. "SAE Corrected" output was 220rwhp. Torque curve is quite flat, with a peak of 186ft-lbs between 5000 and 6000rpm (surprisingly high!). By 7000rpm, torque falls off to 165ft-lbs. Car runs great. A good deal quicker around the streets than a turbo Miata of similar power. Surprisingly, it's not that loud as far as supercharged Miatas goes. Since that big bower is spinning quite slowly, the standard SC whine is much lower pitched and more subdued. And the 2.25" muffler does a pretty good job of hushing things. Boost response is essentially instantaneous. Virtually no difference since the addition of the the extra throttle volume from the big front mount IC. Boost peaks at 10psi around 4400rpm while tapering down to 9psi by redline. The car is still running the original stock clutch (no, really) so I've not testing low end boost response yet for fear of slippage. But I suspect, at WOT, that 5psi is attainable at around 2000rpm with full boost by 3000rpm. When the new clutch goes in, I'll conduct some low rpm testing/tuning on the dyno. Today, all my dyno runs began at 3500rpm with me slowly laying into the throttle. No clutch slippage as far as I can tell. Although, on the way home, my clutch slipped badly in fourth gear. Despite being pleased with the results, I think there are a few bolt-on components that can be improved upon. One is the designed-for-NA header which will soon be replaced with a balls out Boig 4-1 racing header. I'm guessing that the standard 4-2-1 JR header is optimal for maximum power at this flow level. Even at 5psi, with the M45, the BSP 4-1 header seemed to have a top-end power advantage. The other is the stock tiny throttle body which is causing nearly 2" of vacuum (~1psi) between it and the supercharger inlet. More vacuum at the SC inlet means less boost at the manifold. That's going to be fixed asap. I'm sure the rest of the exhaust leaves a little to be desired as well. The fuel rail is also stock. Even with the returnless, fixed pressure fuel rail, peak duty cycles with four replacement 500cc injectors is just 64%, leaving a good amount of room for added boost as predicted. I'm guessing that 235-240rwhp should be attainable with the current pulley arrangement if and when all these areas are addressed. Judging by the results of others, I have big hopes for that Boig header :) Also, all testing done today was with the VICS system turned off (butterflies always open). I suspect having it stay closed at low rpm (controlled by the TEC-II) will result in a bit more low end torque. But that testing/tuning will have to wait for a new clutch. But as it stands right now, the car hauls butt. A good deal quicker than a turbo Miata of similar power. Very responsive with no peaks or dips in the power delivery. Head whips back instantly upon up-shifts. Absolutely no lag. And a lot more driveable as well. Also, with such little top-end roll-off, the shape of the torque curve makes for some surprisingly potent performance when shifting at redline. And that's a common practice considering how lightly stressed the motor seems to be. The car runs with plenty of advance, right at MBT, with the knock no where in sight. Air/Fuel ratios are super conservative consider the recent changeover from 92 to 91 octane. And the fact that the car is currently making exactly the same wheel hp as my 500lb heavier RX-7tt (when it was stock, that is), means the Miata should run most of the big turbo boys. Once the clutch goes in, I'm tempted to even take it to the drag strip and see what it can do. That's it for now. More mods to come, of course. Cheers, shiv

Ford’s new diesel Lion 2.7 turbo diesel has cylinder pressure of 180 bar but expect 220 bar in the future.

BMW V8 with no throttle .. valve spring forces below 500N

basically a 100A relay with a vacuum operated switch plus voltage monitor

to disengage the relay. No turbo or S/C version available ..

ABS car ...

01 480 464 052

Bubble Castor camber gauge

FIA/RAC Specification for Roll cages. Recommended for all competition use

Material - 38mmx2.5mm cold drawn seamless steel tube (CDS2) International events require rollcages to have larger diameter main hoops. Recommended for all competition use. Material - Main Hoops=45x2.5mm/50x2mm CDS2. All other parts=38x2.5mm/42x2mm CDS2

"High boost levels are not all of the answers behind engines failures. High boost and high rpms are not a good thing with a stock engine. But with a good boost controller 18-19 psi at the mid-range and 15 psi at the top end is quite doable on a 135K engine completely stock engine. But I am using water/methanol injection above 12 psi - intake temps remain a few degrees above ambient." Robert Circle <rcircle@erols.com>

"FWIW, actual back pressure numbers may approach 35 psi @ 15 psi intake pressure." DA

"Talked to my engine builder yesterday and they decided to go with rings from Ross instead of Total Seal. I've got Ross pistons and Ross just started offering their own rings. Hopefully they work well" Frank Mowry <fmowry@ngs.noaa.go>

"Regarding that optimum timing curves derived on the dyno are typically too aggressive for the street and may produce knock, a quote from a tuning book says something like, IIRC, "the ramp up should be 30s or longer to get the heat into the pistons so any detonation that may come out will do so"." Jason Cuadra

FM3 wastegates; The Cartech unit has a cast iron diaphagm body and IIRC the Turbonetics has a machined aluminum body.

Running 215 KPA at the dragstrip all last night on 10AE…

"..first gear ('94 torsen rear) at 18 psi spins the tires out of control without dumping the clutch and second gear spins them wildly also. 3rd gear I finally hook up a bit with 215-40 T1 plusses but still get some spinning unless the road is completely flat and warm. The car is pulling hard as hell to redline in 4th and as far as I was willing to go in 5th. We'll see how it pulls mph-wise on the dyno when I do a couple of 5th gear high speed runs. The engine is a mildly ported 1.6 (1.72) with 9.0:1 pistons. I'm running the "turbo default 1" timing still and the most knock I've seen is 22 and that was only in 5th gear at about 6K rpm, 18psi. Numerous pulls to 7K rpm in 4th at 18 psi yielded only a 10 knock count. Still room to play. This is with the latest Dealer Alt. BB T28 turbo, a 2 1/2 down pipe chopped off right under the car to 3 inch cat to 3 inch straight through muffler/exhaust. I'll try and see where I hit 18 psi in 3rd and 4th from about 2500 rpm start after punching the throttle. Good news for old DA kevlar clutch owners. Mine is holding fine, no slippage at all." Frank Mowry

"The turbo housing acts a lot like the expansion chamber of a two stroke motor's exhaust. It's a large chamber directly off of the exhaust manifold that allows the exhaust gas to get out of the cylinder much faster and more completely than a standard header. The turbo then slows down the exhaust velocity, but the immediate effect before the turbo is better cylinder scavenging on the exhaust stroke.

The waste gate is closed at idle but the exhaust section of the turbo isn't a great restriction because it is slowly rotating allowing the gasses a reasonably easy path through.

The exhaust is quieter with a turbo because the turbo's vanes chop up the pressure waves in the exhaust flow into a smooth stream of small pulses rather than the one large pulse of a NA motor.

The back pressure of the turbo doesn't kill a lot of power at cruise (what did Corkey say it took the 99 to cruise, 9-12 hp?) because not a lot of exhaust is being trapped behind. What is trapped is a lot like an EGR valve's addition I believe." MarkC

"For high-boosted track driven turbo Miatas, it may be a good idea to run a heavy mixture of race gas. Then, you can download a specialized track-only calibration file that bumps up the advance angle several degrees. The additional timing should reduce EGTs, send less heat into the engine, lessening the demands on the cooling system. I think it's way too easy with programmable EFI to run too much boost with too much ignition retard. Do it long enough on a track and the engine can very easily "death spiral". This happens when the rising engine temps begin to induce knock. Then the knock sensor jumps in and takes away more timing. Before you know it, the car is running at 12psi with 0 degrees of advance and 1700+C EGTs! Yikes. That will overheat an engine (and/or melt its exhaust valves) in no time." Shiv

FM BOV part number; Mitsubishi part number is MD162219. Mitsubishi calls it an Air Valve,

FM3 inlet filter K&N part # RU-1520.

"I can confirm the merits of Jay Kavanagh’s exhaust manifold. Not only is it the most beautiful one that I've ever seen, it also appears to be very functional. Really good boost response with lots of top end power. I suspect his turbo matching skills also have something to do with the performance." shiv

"You can do a sub $1000 miata setup if you do everything yourself and forego the programmable ECU. You would have to build your own header however and that takes considerable skill. a sub $1000 Miata setup would consist of the following. $150 Volvo T3 Turbo from Junkyard $100 Used Cheezy Intercooler from Audi 5000 $200 tubing $200 various connectors and parts. $125 FMU $125 Fuel Pump retard the timing Then you cuss and work a bunch and have a car that runs less than optimal. Mark From Mark Peugeot

The new product is no longer called DeskTop Dyno, but rather Dyno2000. http://www.motionsoftware.com/products.htm

StreetDyno parameters

drivetrain loss numbers at 0

Frontal Area: 1.5 sq meters ( 17.7 sq ft )

Drag Coefficient: .38 (top up) and .44(top down)

frictional loss: 15% if you want flywheel hp not rear wheel hp (otherwise zero

"I wrote my own version of Homedyno and have used it extensively. See my page http://miataphiltech.tsx.org" Jason

Ric’s ultimate?

The Street Kit Street front mount with 2.5" inlet & outlet (maximum flow) can be used with A/C system 2" in I/C piping with best routing possible 2.5" down pipe super 60 T3 rated & mapped for 350 hp Tial 35mm Waste Gate HKS racing BOV Autometer boost gauge All necessary hose, clamps, oil fitting for turbo oil inlet & outlet line TEC-II Engine management system Plug and play setup.

400rwhp at 26psi.

Motronic wheel; 48 + 1 wheel as opposed to the 60 - 2. The 48 + 1 does not have an 18 degree blind spot

Ric is using a T3/T4 hybrid for 400rwhp

Street front mount with 2.5" inlet & outlet (maximum flow) can be used with A/C system

2" in I/C piping with best routing possible

2.5" down pipe

super 60 T3 rated & mapped for 350 hp

Tial 35mm Waste Gate

Tubular exhaust manifold

HKS racing BOV

Autometer boost gauge

All necessary hose, clamps, oil fitting for turbo oil inlet & outlet line

TEC-II Engine management system Plug and play setup.

Ric 350hp street T3 turbo kit inc TecII $3475

Ric 400hp race T4 turbo kit $3675 + shiv tecII kit $2475 = total $6150

Mark’s ultimate

> head work Yes. > rods Carrillo > pistons (CR?) 9:1 > port matched Yes > SWAT exhaust manifold Yes > T3/T4 T-4 Straight. > Tech-II Nope, Haltech > 3" exhaust > What will you use for intake? VICs? Custom Intake and Exhaust. > > Do you plan to run 8 injectors (can Tech-II handle 8) > or 4 large inj.? 4 Injectors (550 or 720 cc) > One or two line fuel supply? Two line. > Obviously a larger fuel pump? Pierburg

380hp Link car

1884cc (1 mm over)

9:1 compression JE pistons

Carillo rods

port/polished head

balanced and blueprinted w/ flywheel and pressure plate

Motor work is done by Benson's Machine Shop

extrudehoned intake

RC 560 injectors

Inline high pressure Piersberg fuel pump

Tial wastegate

FM Racer radiator

BEGI Racer IC

ACT Extreme pressure plate and high performance sprung clutch

T3/T4 turbo

Ron Tsan http://home.earthlink.net/~jessmx5/

1990-97 FM II

Garrett T28 water-cooled turbo

standard turbocharger: 0.48 A/R compressor, 0.64 A/R turbine

small ball bearing option:0.80 A/R compressor, 0.64 A/R turbine

large ball bearing option:0.60 A/R compressor, 0.64 A/R turbine

16" x 8" x 2.5" intercooler

2.5" downpipe

440 cfm injectors

standard Mitsubishi blowoff valve optional FM all-metal sequential blowoff valve

"1.8L (stock motor - Just picked up from a used Japanese motor place)

Turbonetics T3/Super 60 BB with Stage 5 turbine wheel.

Bell Engineering Cast manifold

Turbonetics Deltagate Wastegate

2 1/2 in downpipe to 3" custom exhaust

Spearco Front mount Intercooler 2" in and 2.5" out

XS Engineering Blow off valve

K&N filter

550 CC RC Engineering Injectors

FM programmable ECU

15 PSI @ 285HP at 7100 Peak torque at 5100

This shows the very large stage 5 turbine wheel. Could make more power with a stage 3 wheel, but the car spends most of its time between 5500 and 7400 rpm so the stage 5 seems ok. Might try a stage 3 sometime if I get a bug. " Bill Lackey race car

"FWIW, Tommy, a friend of mine has the unofficial record for the worlds fastest 1.8 Audi A4 Avant. It's a 1789cc engine running 2.9 bar (42,6 psi), and his latest dyno run gave 427.7 kW @ 6.950 r/min, and 634.4 Nm @ 6.190 r/min. We measured top speed in Sweden using a GPS and one helluva straight, 321 km/h :) Not too bad for a station wagon! I don't know all the details about the engine, but not a lot is left stock. The injection system is the stock Audi system, though. Just remapped. Apparently the Audi system is very flexible and has better resolution that any of the aftermarket systems. It even decreases boost if the intake temps get high. The turbo is a pretty huge KKK unit, and he has a water cooled intake on the turbo, to make sure intake temps are as low as possible. If I remember correctly he has had 11 engine failures getting where he is now, and so far this adventure has cost him about $120.000 + the cost of the car! That was not on pump gas BTW, race fuel... Impressive non the less..." Espen

Cracks will likely form at the wastegate. Header cracking due to cyclic thermal stresses (thermal fatigue) typically occurs in the collector region over time. Cracking elsewhere may be indicative of other issues. So far, so good. I've been running it hard, daily, with no issues for a few months. In fact, I haven't had to remove the header or turbosystem even once since I installed it. Jay

http://albums.photopoint.com/j/AlbumIndex?u=914444&a=13994372 are the piccies of Jay’s turbo

Yep, 321 stainless. A friend of mine did the welding; we've discussed doing a run of headers, but he's not interested (bigger fish to fry).

It is a Tial External WG with a .65 bar spring which is 9.5lb - goes to mid to low 20lb The wg starts to open then.

T04 = T4. A T3/T4 hybrid uses a T3 turbine (exhaust) section mated to a T4 compressor (intake). The two popular T4 designs are: T04B is a mid-80's design. T04E was designed later and benefited from experience with the T04B. These are Garrett designs and are marketed under other manufacturers (AirResearch, Turbonetics, etc) Note that the TD04 turbo (made by Mitsubishi) is not a T4 unit.

Espen ran 22psi on a T28 1.6

"TechCraft is currently in the process of building a no-holds-barred Miata motor for me and my brother. Should be done by year end. I'd be surprised if it couldn't surpass 400bhp." Shiv Patak

"Well there is a difference between using a compressor and a blower. As odd as it seems, the "compressor" squeezes the air inside the air pump before letting it out. The blower doesn't compress the air inside, rather it waits until it shoves it into the manifold. The significance of this difference is the 15 to 20% gain in thermal efficiency for the compressor." Corky

Extreme Motorsports website ; Stainless Steel O2 Housing w/Tial Wastegate -