- Water injection; work with the fitted Aquamist to allow me to raise the equivalent octane number of the petrol. This will suppress knock and allow me to run more aggressive timing on cheap fuel for more power. The next stage is to increase the boost pressure (currently 14.5 psi on stock engine) and so increase power output. Update; I have not found a lot in this system but have only done rudimentary tuning work so that may be expected. Bill Cardell has found more knock resistance after adding timing to get the power back (initially it is lost at pre water injection timing settings).
- Cylinder work; get cylinder head ported or just gas flowed (gas flowing is just knocking the sharp edges off while porting is removing substantial amounts of material to alter velocities of gas and hence achieve far greater increases). The porting has been done by SP Performance Centre who are talking of trying to increase the inlet valve diameters by 2mm and I am looking at cams. This is with a Mk2 cylinder head .. this is superior to the Mk1 as the valves are bent over to straighten the air flow path. Update; SP Performance have a ’99 cylinder head to play with – to be base lined and then we will work on the possible advantages of bigger valves and higher lift cams. Gained 14% flow on this head which is better than a Mk1 so maybe 17% gain straight to the back wheels if fitted. I am now considering cams and valves. This will be fitted to my Dubai car...
- Air intake; FM3 intake and Sebring BOV fitted – not sure how long BOV will last but so far about 6k miles.. FM dropped them soon after supplying mine. The air filter is much noiser.
- Engine - non head related; Build the engine – after market con rods and pistons with a full balance. I can get a package from a piston/con-rod broker in the US for about $1k.
- Exhaust; remove the Cat as I do not need it for MOT purposes .. I have now got 2 silencers in my custom 2.5" SS. The cat replacement with test pipe will give more power but allow cat replacement as required for noise/emissions. End pipe needs polishing to remove visible welds.
- Roll protection. Currently exploring a combined double hump style bar type arrangement but with the strength of a proper Hard Dog roll bar. The standard/unbraced Hard Dog roll bar is very weak; 400 kg would push it over .. and the car weights 1070 kg! I would like to be able to withstand twice the vehicle weight so I am shooting for a 2000 kg load at top of hoops in any direction. This can be achieved with 2.5" 1.6mm tube in SS but this size of tube is difficult to fit in with my glass rear window. This is also a problem with the hard dogs roll bars; you need a Mk2 rear glass and suitable frame. The Hard Dog is made from 1.5" 3.2 mm walled tube but it only has a yield of 200 N/mm^2, with the SS tube you can push the yield up to 360 N/mm^2 and this combined with larger diameters give a frame of half the weight but four times the strength. (Funnily enough the style bar I got with the car (Power Up by ?? Japan) was very similar but the hoops were so large that you could not get past them to the roof while in the driver’s seat – I plan inverted U’s rather than inverted V’s)
- Draught protection; fit mesh to roll hoop centres, material to the bottom edge and a clear removable section in-between the hoops to provide a wind stopper. Mike Satur is developing this concept with black coated roll hoops and cast aluminium carrier frame. Currently have a £10 DIY concept that works well and packs down to something about 2" in diameter and 8" long…
- Brakes; currently I have 1.8 brakes (funny that… it is a 1.8 car!) on the rear with EBC Greenstuff pads. I have FM big brakes which have Wilwood 4 pot calipers and bigger discs on front. These comes with SS brake lines. ABS valve fitted. I am not totally happy with the balance on this car still .. need to experiment without rear valve fitted. Ultimate would be to have 4 channel switchable (i.e. off switch!!) ABS off a Mk2 … and maybe even add a load compensation valve on the rear axle .. but this is all major major stuff. Latest trick I’ve heard is to remove the rear pressure control valve .. and fit FM big brake rotors at the rear with ’91 RX7 turbo calipers..
- Heat flow control!; I need to replace the engine undertray and remodel around the intercooler to improve the % going through the radiator and hence it’s efficiency. I might fit a SS grille after this…but with or without tow hooks!
- Finish the interior .. electric windows auto up and down on all functions… oh and lighted interior mirror would be good! ..shorten the gearstick for a short throw gear change … remove more material from seat backs to gain more leg room?
So much to do .. and work too!
.. and now I have this car in storage while working overseas in Dubai where there must be about 6 to 10 Miatas total … and I have plans to build a new car;
- US ’94 1.8 with LSD as standard
- Suspension – KYB’s with ground control (adjustable perches for springs and 2.5" springs), FM sways, powerflex bushes, hemi links for sways (anti-roll bars in UK), same 215-40-16 wheel/tyre combination but maybe more expensive rims and less rain tolerant rubber
- Engine – ’99 gas flowed head, maybe with big inlet valves and Kent cams for lift etc by SP Performance/ Kent cams, Pauter rods, J&E pistons with 9:1, split edged crank with polish, all balanced, light flywheel, 3" exhaust, Tail wastegate, ? BOV, T3 or close turbo with 14.5 psi by 3,600 and maybe 19-25 psi top with a target of 350-380 hp (about 310-340 rwhp) to keep up with stock TVR Tuscans (4 litre, 380hp and same weight), TecII engine management. FM rad and radical flaps to keep a/c working
- Transmission – for HP/torque I may have to fit most of an RX7 transmission – still an MX5?? .. even more money would fit a Supra gearbox. 8" RX7 diff also needed.
- Brakes – FM fronts with straight through rears, maybe RX7 with transmission (5 stud wheels)
- Paint … it has to be yellow .. Yellow Peril No. 4
- Stereo – Becker head unit with CD & RDS, Genesis amp maybe, Dynaudio speakers again .. with a Miata I will have head rest speaker..
- Roll over protection – custom?
- Rear glass window off my UK car (it has a Mk2 roof already)
- Leather seat kit – maybe but sun makes this too hot.
Anyway … all dreams so far!