Quote:

I ran a best of a 13.55 @ 89mph with 3.23's and 235-60 tires. I installed 4.10's and 29X10.5" slicks and ran a best of 12.71 @ 106mph.

I think that is a little better than average. I have heard that you will only gain up to a half second with a gear change.



something doesn't add up....what else did you change on the car? there's no way you picked up 17 MPH with just a gear change. your MPH should be pretty close to the same independent of gear ratio.

assuming 29" tall tire, and no converter slip RPM at 70 MPH will be 2620 for 3.23's and 3175 for 3.91's I'd assume 5-7% slip, which would raise the RPMS to 2750-2800 RPM's for the 3.23's and 3334-3400 RPM for the 3.91's.


Last edited by patrick; 04/23/09 12:30 PM.
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