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WILMASBOYL78
09-18-2019, 06:27 PM
225 x 70/14 tires....60 mph is 3200 rpm in high gear

what is the rear gear ratio?

thanks..wilma

Keith Seymore
09-18-2019, 06:48 PM
Assuming a diameter of 26.4 inches for a P225x70/14 tire

https://www.differentials.com/technical-help-2/differential-gear-ratio-calculator/

I get 3000 engine rpm at 60 mph for a 3.73 ratio;

3300 engine rpm at 60 mph for a 4.10 ratio.

I suspect that does not comprehend auto trans converter slip, etc.

What kind of rear end? That will affect our library of available discreet rear axle ratios to choose from.

K

WILMASBOYL78
09-18-2019, 07:19 PM
it is a 12 bolt chevy in a 69 camaro...muncie 4 spd.

thanks

ssl78
09-19-2019, 01:38 AM
I would say 4:10 I have a 4:10 in my Camaro with F70x14 and I do around 32000 at 60 mph

Keith Seymore
09-19-2019, 11:18 AM
I would say 4:10 I have a 4:10 in my Camaro with F70x14 and I do around 32000 at 60 mph

That's spinning it pretty fast.

K

mssl72
09-19-2019, 08:21 PM
32,000 RPM!! That is hauling!