The general rule I was raised on is when attempting fastest possible acceleration, upshift at redline.
However, since this is my first turbo car, and first experience with torque peaking much earlier in RPM range and falling through HP peak on Dyno plots, plus peak HP is well below redline, I wondered whether the Fist should be shifted differently for max acceleration.
Plus my butt dyno had me shifting 3rd-4th and 4th to 5th gears on track around 5500 rpm rather than at redline.
So I used one of my stock turbo 3rd gear Cobb S3 logs and a spreadsheet to obtain tables of torque and hp by gear and by rpm. Graphed both.
Turns out the answer is upshift at redline for max horsepower in every gear. For example, at redline in 3rd gear, car is putting around 240 hp to wheels at redline, which is more than any hp available at any rpm in 4th gear. On this particular log, peak hp calculated for 4th gear is 208 at 5500 rpm.
Going by torque alone, shifting a little earlier 3/4 and 4/5 should work better.
But extracting max HP through the gears should be the best strategy for max acceleration.
Alternatively, I blew the analysis on theory and there is a better answer. Just curious, probably too many variables to test it on a circuit, maybe a drag racer can opine?
However, since this is my first turbo car, and first experience with torque peaking much earlier in RPM range and falling through HP peak on Dyno plots, plus peak HP is well below redline, I wondered whether the Fist should be shifted differently for max acceleration.
Plus my butt dyno had me shifting 3rd-4th and 4th to 5th gears on track around 5500 rpm rather than at redline.
So I used one of my stock turbo 3rd gear Cobb S3 logs and a spreadsheet to obtain tables of torque and hp by gear and by rpm. Graphed both.
Turns out the answer is upshift at redline for max horsepower in every gear. For example, at redline in 3rd gear, car is putting around 240 hp to wheels at redline, which is more than any hp available at any rpm in 4th gear. On this particular log, peak hp calculated for 4th gear is 208 at 5500 rpm.
Going by torque alone, shifting a little earlier 3/4 and 4/5 should work better.
But extracting max HP through the gears should be the best strategy for max acceleration.
Alternatively, I blew the analysis on theory and there is a better answer. Just curious, probably too many variables to test it on a circuit, maybe a drag racer can opine?