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Old 09-29-2013, 01:22 PM
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Bill Hanlon Bill Hanlon is offline
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Join Date: Feb 2005
Location: Fredericksburg, TX
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Quote:
Originally Posted by low63gp View Post
Guys,

I have found that my car speedp is running 95 mph at a true 70 mph and the tach is at 3200 rpm.
I think it is due to smaller tires. Does anybody know the calculation of gain in mph on speedo if I change fron 3:23 to 2:69?
It looks like that is what I plan to do. Im just wondering what my new true mph adjustment would be at 3200 rpm with that gearing increase.

Also, if anyone has a 2:69 from 61-64 I am interested if you are within 500 miles of Central California.

Thanks,
Mike
Assuming your 70 MPH true number is correct and was taken at 3200 RPM with your 3.23, changing to a 2.69 rear gear would give you 84 MPH true at the same engine speed.

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