'69 Corvette gear ratio
 

How can I find out what the original gear ratio was in a '69 Corvette? It's a 390 HP 427 with a 4 speed and it has 4.56 gears in it now. I have the rear end out for repairs. It belongs to my uncle and he is thinking of changing the gear ratio. The speedometer is way off and it's not much fun to drive very far.

Freddie -- check a stamping on the bottom of the rear end housing, just forward of the cover ... check out this site for codes. TAZ

http://www.corvettec3.ca/axle.htm

Freddie, I used to have a 390hp 69 Corvette 4 speed with air-conditioning, the default ratio was 3.08 to 1. I believe the same combination w/o air-conditioning was 3.36 to 1, Rob.

If it has the original speedo driven gear you can get the color and go the the gear chart and find out the rear ratio.

Thanks for the replies. I was wondering where the stamp would be. I'll check the code and see what it is. I have a 3.08 gear if that is what it turns out to be.

I would also post on the Corvette forum

Code FA, which is for a 3.70 heavy duty with the 427. This explains why the speedometer is off so much. Thanks for the help.

That's the steepest gear you could get on a 427/390. It would be a fun combination.