What RPM am I turning? Here is the tool to give you the answer.

[Rickf1985]

I always hear " I have no power" or "I have no idea how fast my engine is turning" or "will I get better gas mileage with a double triple overdrive so I am only turning 900 rpm at 75 MPH? Lower RPM is better mileage right?"

Well here is the tool you need to get the answers before asking those questions. All you need is a tape measure to measure the height of your rear tires from the ground to the top of the tire. NOTE the transmission ratios at the bottom of the page for standard overdrive ratios.

http://www.crawlpedia.com/rpm_gear_calculator.htm

And here is another one that will do just about everything for you. For those of you running overdrive transmissions, this figures it automatically at a .70 overdrive. That is pretty close to what most of them have. If you want to do it on your own you can further down.

https://www.ringpinion.com/calculators/Calc_RPM.aspx

[tmsnyder]

Almost 3000 rpm at 65mph for mine, matches up with my spreadsheet calculations.

[cook elandan]

Thanks.