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Vic Santos · 06-23-2011, 05:47 PM

Joe, here is my theory. First maximize the HP put to the track in high gear by gearing the car to go through the eyes at approx. 10% above the dyno peak HP rpm. Next choose a convertor that flashes 150-250 rpm above the dyno peak torque rpm. The 1-2 shift is done at the track by testing. Shifting early (below the peak HP rpm) takes you back into torque multiplication in the convertor while in the high torque rpm's. You are trading HP for more torque at the wheels early in the run. This usually helps ET. The 2-3 shift should be such that the engine falls to approx. 10% below dyno peak HP rpm. The result is that high gear (the one you spend the most time in) goes from -10% to +10% of dyno peak HP rpm.
Testing is the hard part. You need good shift points and good data (air shifter and data logger) as well as good traction and a good valve train.
Good luck, Vic

06-23-2011, 05:47 PM	#7
Vic Santos Junior Member Join Date: Dec 2008 Posts: 27 Likes: 0 Liked 14 Times in 2 Posts	Re: gear shift and the dyno Joe, here is my theory. First maximize the HP put to the track in high gear by gearing the car to go through the eyes at approx. 10% above the dyno peak HP rpm. Next choose a convertor that flashes 150-250 rpm above the dyno peak torque rpm. The 1-2 shift is done at the track by testing. Shifting early (below the peak HP rpm) takes you back into torque multiplication in the convertor while in the high torque rpm's. You are trading HP for more torque at the wheels early in the run. This usually helps ET. The 2-3 shift should be such that the engine falls to approx. 10% below dyno peak HP rpm. The result is that high gear (the one you spend the most time in) goes from -10% to +10% of dyno peak HP rpm. Testing is the hard part. You need good shift points and good data (air shifter and data logger) as well as good traction and a good valve train. Good luck, Vic