A friend complained about the transmission shifting down too eagerly with light pedal. I checked the tune and it was nothing like he described. I logged the car and noticed the downshifts occurred in very different speeds than the table said. Then I looked the pedal position and found the culprit: Pedal goes from 0 to 159% and the blade reaches 100% when pedal is at 70%.
Because the pedal percentage isn't adjustable, I'm wondering what is wrong and how to proceed?
The car is a C4 Corvette with a truck engine. Log of the pedal movement attached and the tune also.
The trucks the PCM came from were available with either adjustable or non adjustable pedals. There have been many many posts with this problem and I have not seen anyone solve it or explain exactly what mismatch causes it. Something about the swept range of the APP and PCM/TAC calibration is different between adjustable and non.
Since this is a swap and the PCM OS doesn't need to match the rest of the vehicle, I'd suggest changing to an OS from a platform that never offered adjustable pedals.
Reply With Quote
