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The MKV A90 Toyota GR Supra was a divisive car when it launched back in 2019, to say the least. Its predecessor, the MKIV Supra, had become a JDM cult hero in the early 2000s, with the infinitely tuneable 2JZ motor becoming the gold standard in everything from drag racing to drifting.
Despite being a very capable sports car, the A90 Toyota Supra was still derided at the time for essentially being a BMW Z4 with a fixed roof. Four years on, however, the car community has seemingly embraced the MKV, with numerous crazy builds coming out of the woodwork. YouTuber and Pro Drifter Adam LZ is no stranger to crazy project builds, but this time, he’s trying to keep things a bit more civilized by turning this A90 Supra into an automatic daily drifter.
MKV Toyota GR Supra Gets More BMW Parts
After buying and fixing this crashed Supra, Adam wanted to keep the 8-speed automatic transmission and, with the help of Polish tuning outfit HGT, managed to convert the original transmission to have a working clutch pedal.
Having a clutch is vital for drifting as it allows the driver to ‘clutch kick’ the car – spiking the revs to increase the rear-wheel speed to either initiate or maintain a drift. Unfortunately for Adam, the original factory 8-speed eventually broke and needed replacing. Adam had 3 options – fit a replacement 8-speed OEM transmission, an OEM 6-speed manual, or go for a 7-speed DCT transmission from a BMW.
He decided to go with the latter, saying that the DCT would be a stronger, more reliable option than the 8-speed while still keeping the car usable as an automatic daily drift car. He doesn’t mention which specific gearbox he is using, but we speculate that it is the 7-speed M-DCT from either an F82 M4 or an F87 M2.
Getting A Dual-Clutch Transmission Supra To Work Isn’t Easy
Polish outfit HGT is once again helping on this project, with them fitting their transmission control module dubbed the GCU. From there, Bartek from HGT sets about tuning the GCU transmission software. The software has to calibrate all the solenoid valves in the transmission that operate both clutches and how they should respond to the engine input. This requires a lot of patience and a slow build-up – starting from first-gear bite-point rolls all the way to full pulls in higher gears.
After half a day of tweaking, Adam can finally get behind the wheel and give the Supra some proper drift testing. Adam is very impressed with the feel of the transmission and says it changes the Supra’s character significantly. However, the upshifts are still a bit laggy, and the ECU appears to cut the throttle on flat shifts.
After some investigation, Adam finds that when the transmission is shifting, the car is over-boosting, causing the ECU to cut the throttle as a safety measure. This isn’t a quick fix and requires some deep-dive ECU tuning. The whole process is fascinating and goes far too in-depth for us to fully cover here, so we recommend checking out the full video for all the technical details.
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