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gilmoujr · 07-31-2002, 05:38 PM

the formula for calculating the speed for the RPM's is this:

Apply it to any tire size, gear ratio, tranny ratio, and RPM:

TIRE = Tire size (calculate from previous post)
REAR = Rear Gear (ex. 3.73)
TRAN = Tranny Ratio (3.38, 2, 1.32, 1, 0.67)
RPM = Obvious

(60 x RPM) / (5280 / (TIRE x 3.1419/12)) / REAR / TRAN

A specific Example is:
TIRE = 25.68
REAR = 3.27
TRAN = 3.38
RPM = 2300

(60 x 2300) / (5280 / (25.68 x 3.1419 / 12)) / 3.27 / 3.38
15.9 MPH

If I am in error, I apologize, but I think this should work for us Tremec 3650 owners. I have put together an Excel Spreadsheet that calculates everything for you (you just plug in the tire numbers and rear gear). If you want a copy of it, let me know and I will get it out to you.

Jim

07-31-2002, 05:38 PM	#1
gilmoujr Registered Member Join Date: Mar 2002 Location: Dexter City, Ohio Posts: 60	One more and I'm done - 3650 Analyzer the formula for calculating the speed for the RPM's is this: Apply it to any tire size, gear ratio, tranny ratio, and RPM: TIRE = Tire size (calculate from previous post) REAR = Rear Gear (ex. 3.73) TRAN = Tranny Ratio (3.38, 2, 1.32, 1, 0.67) RPM = Obvious (60 x RPM) / (5280 / (TIRE x 3.1419/12)) / REAR / TRAN A specific Example is: TIRE = 25.68 REAR = 3.27 TRAN = 3.38 RPM = 2300 (60 x 2300) / (5280 / (25.68 x 3.1419 / 12)) / 3.27 / 3.38 15.9 MPH If I am in error, I apologize, but I think this should work for us Tremec 3650 owners. I have put together an Excel Spreadsheet that calculates everything for you (you just plug in the tire numbers and rear gear). If you want a copy of it, let me know and I will get it out to you. Jim