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Twin Turbo IS-F

I did a twin turbo kit on one of the first cars released in texas back in feb. and mar. 08. The car was a development car intended on seeing if it was feasible to release a bolt on turbo kit to the public. While the car was finished and is still turbo'd today it was basically determined that we couldnt release it for the price we originally wanted to and what we could do it for was over what owners would be willing to pay. We also werent able to reliably keep the check engine light off. It came on for little things like the MAF reading out of its range because of too much airflow.

The car has a traditional turbo setup in the sense that the turbos are immediately after the headers. The benefits of this are that turbos work off of the heat and expanding gasses of the exhaust, so a remote setup looses much of its efficiency. Also it keeps the intake tubing short making it quicker to pressurize. The car runs on the stock computer before it sees boost to maintain drivability and all that good stuff. When it goes into boost a motec m48 controls a second fuel system injecting into the ports above the stock port injectors. The motec also handles boost control.

The build on this car was extremely tight which also added to the increased cost of the kit. After building it we determined that it was too much work for the average consumer to do themselves, so we would have to perform the labor to install the kit.

As for the reliability and power of the car they both turned out to be surprisingly good. The engine internals and transmission are still stock and have never shown any signs of weakness. The build was done when the car had only 800 miles. Now the car has over 6000 and has never had any problems mechanically. The electronics are another issue, fighting them is a nightmare. If anybody does come up with a way to get into the stock computer and be able to tune the car, it would knock out a significant portion of the price that would be associated with this "kit".

Anyway the car currently lives everyday at 600 crank hp with no mechanical issues and very few electronic issues. It is set at 6-7 lbs of boost, but i have made a higher boost dyno pull with it and laid down 600 at the wheels. One problem we believe we have been running into is that the stock computer has built in slew rates for each gear which it compares the engine rate of acceleration to. If it thinks it is running away it will close the throttle even if you have it wide open. This is a safety feature put in by the smart guys at the factory to help prevent blown up engines, too bad it kinda puts a damper on our objectives.

So there you go. A little insight on the limits I have seen so far with this car.

And for those of you who dont believe me, here are a couple pictures of the build.


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