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blue2000s · 06-14-2006, 07:35 PM

I've seen a few posts on the board asking at what RPM to shift for maximum acceleration. The answer is, for any given vehicle speed, the engine could be making a certain amount of torque to the wheels in each gear. The goal is to use the gear that's making the maximum torque at that speed. It's not just a matter of the engine torque but a combination of engine torque gear ratio and vehicle speed.

To illustrate, and for you curious folks, I've attached a spreadsheet that does all the calculations for you. You need to input tire information and engine torque.

As you can see, at any given speed the wheels are getting the most torque from the engine in the lower gear up to redline up until 4th gear, where there is a slight advantage to shifting into 5th a little before redline at about 114 MPH. 5th to 6th similarly has a very minor shift point benefit before redline.

download and delete the .txt from the file extension, it's a .zip file.

06-14-2006, 07:35 PM	#1
blue2000s Porscheectomy Join Date: Mar 2006 Location: Seattle Area Posts: 3,011	Shift Points for Maximum Acceleration I've seen a few posts on the board asking at what RPM to shift for maximum acceleration. The answer is, for any given vehicle speed, the engine could be making a certain amount of torque to the wheels in each gear. The goal is to use the gear that's making the maximum torque at that speed. It's not just a matter of the engine torque but a combination of engine torque gear ratio and vehicle speed. To illustrate, and for you curious folks, I've attached a spreadsheet that does all the calculations for you. You need to input tire information and engine torque. As you can see, at any given speed the wheels are getting the most torque from the engine in the lower gear up to redline up until 4th gear, where there is a slight advantage to shifting into 5th a little before redline at about 114 MPH. 5th to 6th similarly has a very minor shift point benefit before redline. download and delete the .txt from the file extension, it's a .zip file. Last edited by blue2000s; 06-28-2006 at 12:14 PM.