RPM to MPH Calculator From C5Registry Member Torrey Horn

Here's a Microsoft Excel 97 spreadsheet with some charts and graphs on the RPM to MPH conversions on it for manual and automatic transmissions. You can change the tire sizes and gear ratios, etc.

I used a 35 series tire in the calculations, as you don't actually get 40% sidewall with a 40 series tire (some of the sidewall overlaps the wheel rim.) 35% seems to work with the P275/40SR-18 tires on the rear, and gives a 25.5 in. diameter, which I checked with a tape measure to be sure.

The spreadsheet is in Excel 97 format, so if you would like it in another format, let me know. There are two tabs at the bottom, one for Manual transmissions, and one for Automatic transmissions. You can change the rear end ration for the auto, to put in whatever rear end ratio you have in your car.

To download the WinZip'd File Click Here [rpm2mph.zip]

Torrey Horn  EMAIL hoto@chevron.com

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