manual shift points....
manual shift points.... always remember hearing there is a general area/rpm that you should shift at according to your peak hp/torque. how exactly was it put? Just looking for a starting point since i have my dyno sheets and haven't been out racing a 6speed in a while 
thanks
Chris
thanksChris
On The Tree
Joined: Jan 2004
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In the book "Auto Math Handbook: Calculations, Formulas, Equations and Theory for Automotive Enthusiasts" by John Lawlor he suggests that the ideal shift point should occur 10% past the RPM where you make your most horsepower.
For example on a car that makes peak power at 5,000 rpms you would shift at 1.10 x 5000 = 5,500 rpm.
For example on a car that makes peak power at 5,000 rpms you would shift at 1.10 x 5000 = 5,500 rpm.
I can't remember the source, but the way I read it explained was:
Using your engine torque curve and gear ratios, figure out the amount of torque you're putting to the wheels throughout the engine rpm range in each gear. Using 1-2 shift as an example, as you go past peak torque and torque falls off in 1st gear, you want to shift at the point where the torque at the wheels in 2nd gear is greater than the torque at the wheels when you left 1st gear. This calculation has to take into account the rpm drop during the shift, which puts you at a lower rpm on your engine torque curve AND your torque to the wheels will be calculated with the new gear ratio (2nd gear is a lower multiplier than 1st gear). With that being said, every calculation I've done for these cars shows the desired shift point to be well past the point that I want to rev the motor to. So I'd second 01-Z's response: "As high as possible." But you've got your dyno sheets and you know your gear ratios, so you can see how your numbers add up.
my $0.02
Using your engine torque curve and gear ratios, figure out the amount of torque you're putting to the wheels throughout the engine rpm range in each gear. Using 1-2 shift as an example, as you go past peak torque and torque falls off in 1st gear, you want to shift at the point where the torque at the wheels in 2nd gear is greater than the torque at the wheels when you left 1st gear. This calculation has to take into account the rpm drop during the shift, which puts you at a lower rpm on your engine torque curve AND your torque to the wheels will be calculated with the new gear ratio (2nd gear is a lower multiplier than 1st gear). With that being said, every calculation I've done for these cars shows the desired shift point to be well past the point that I want to rev the motor to. So I'd second 01-Z's response: "As high as possible." But you've got your dyno sheets and you know your gear ratios, so you can see how your numbers add up.
my $0.02
