Bit of background to begin with. I bought my Toyota MR2 about March 2004, it was a Nov-2002 model, white, 6 speed, sequential manual transmission [SMT] (for those who have not seen the MR2 Spyder, its essentially a manual transmission with a computer controlled clutch and a sequential shifter instead of an H-pattern). I had owned another Spyder before then which was a brilliant yellow, unfortunately, got stolen within 30 days of owning it from my own garage! So the white one was a replacement.Anyway, the MR2 Spyders are an exceptionally well balanced car, extremely responsive handing,
but the major problem I saw was the lack of grunt... It typically puts down about 105hp to the wheels without modification, and runs a 15.8 second quarter mile, on a good day. The other problem is the lack of control over the clutch with the SMT. Typically, a mid-mounted rear wheel drive car is a perfect platform for carrying out quick launches, however, without the control of a clutch, it is typically impossible to launch. The closest thing you can get to a launch is to do a neutral drop... and we all know how quickly that destroys the transmission! *I have tried it a few times!
but the major problem I saw was the lack of grunt... It typically puts down about 105hp to the wheels without modification, and runs a 15.8 second quarter mile, on a good day. The other problem is the lack of control over the clutch with the SMT. Typically, a mid-mounted rear wheel drive car is a perfect platform for carrying out quick launches, however, without the control of a clutch, it is typically impossible to launch. The closest thing you can get to a launch is to do a neutral drop... and we all know how quickly that destroys the transmission! *I have tried it a few times!
So after the factory warrenty expired, I decided to throw some cash at some performance mods... namely, a Hass Turbo Kit, developed by Jay Hassinger over in the USA. This kit has been well received by the Spyder community, and has typically put down around 210whp at 8psi or so, on stock internals of a 10.1:1 compression engine. Given that the Spyder only weighs around 990kg, thats great power to weight ration right there! So I got the kit and with the assistance of a friend, we managed to install this kit. The installation pretty much went off without a hitch, the car started right up, not much tuning issues... the exhaust was the biggest issue, where the pipes refused to stay on the hanger for more than 20 minutes of rough driving at a time. At first I didnt realise this, but all of a sudden, I would hear the exhuast note change from a deep rumble to a metallic vibration... By the time I realised what was going on, the exhuast had melted some plastic off a SMT transmission pressure pump! I was lucky it didnt go all the way through!
Anyway, besides the exhuast issue, there were no other apparent mechanical issues... until I got it onto the dyno. At base boost of 6.5psi, it dynoed at a measley 140whp... and at high boost of 8.5, I only managed 174whp... the torque and power curves were the ugliest things I've ever seen, with huge dips at around 4500-5200rpm, then again at 5500rpm to 6000rpm. I eventually managed to tune the dips out and squeezed 180whp out at 9.5psi. Unfortunately, it never made it to 210whp at 7.5psi!
So I went about investigating this, and surely enough, found a few sources of boost leaks, corrected those... however, the setup never managed to hold more than 5psi of boost using a test by pressurising the intake. That problem was never resolved. One day, I got a bit keen, and decided to put the car on the dyno again to see if I can flatten out the torque curve and get that magical 200whp... well, you can probably guess what happened... KABOOM!
Ok, so not exactly KABOOM, but more... PSSSSST... oh sh!t... turned engine off, turned it back on again... TICK TICK TICK TICK TICK.... Some engine internals went obviously! Anyway, that was about 2 months ago, now the car sits in the garage, waiting for its next evolution.
So what is Dean's poor spyder going to have done to it now? Well, part of my tuning woes with the turbo setup was an inability to read ignition timings of the stock ECU. Mr Toyota (Mr T) got lazy and decided not to make the ECUs for Australian cars OBDII compliant. Therefore, to get any decent readings, one would have to invest about $9000AUD to buy a Toyota Genuine Rip-off handheld scanner, or pay 90 Toyota Genuine Rip-off dollars to a dealership to just get a reading. So to rectify this, I decided that I will need to replace the factory ECU with an aftermarket one, specifically the Apexi-PFC.
Great plan, but there is only one problem with that plan, its the SMT. The SMT has its own computer onboard, however, this computer is connected to the ECU, so I will break the SMT system if I replaced the ECU with an after market one, as the after market ECU will NOT talk to the SMT computer.
All this, and a ticking engine, lead to start a project, that has now evolved into something that is quite significant in size... here is what I am planning to do:
* Take out the engine, tear it down, and replace all critical internal components with forged parts and use a lower compression piston to enable running of higher boost
* Take out the SMT computer and all SMT components and modify the gear box to act as essentially a manual gearbox. That is, after the project is done, I will have to use the normal H-pattern to shift gears and have control of the clutch using a clutch pedal! I will also be able to shift faster than the SMT system (that skill has still yet to be developed, but I am sure I'll get there!)
* Replace the factory ECU with the Apexi-PFC. This will be piggy-backed with the GReddy eManage Blue! This is a first as far as I can tell! I will use the PFC to try to minic the tune of a stock ECU, then use the eManage to tune for boost as the eManage has a MAP-Sensor.
What does all this equate to?? Well, besides $$$$$$$$$$$$$$, once all is said and done, I should be the proud owner of a MR2 Spyders with manual transmission and an engine capable of delivering 300hp to the wheels (probably more based on some educated guesses). I suspect I will need a neck brace to keep my head on when I jump in this car!
So this is the start of my journey, and if you decide to follow this thread, its gonna be one hell of a ride!
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