CoolRidge69Vette

O.k. I have a stupid question. As I have never had to do it, is there a way to determine what your rear gear ratio is without examining the actual rear end, counting gear teeth, etc? Is it evident through the VIN number or supposed to be printed on the door tag or somewhere else??

Thanks.

Durango_Boy

Yeah, you mark your tire, make a full revolution, and count how many times your drives shaft turns, with it marked as well.

The number of times the drive shaft turns, will roughly show you the gear ratio.

CoolRidge69Vette

o.k. I'll try that. I understand that process will get me a rough approximation that I can assume fairly accurately to the nearest half revolution or maybe to a bit smaller degree than that, but to match it against what is actually in the car Durango Boy, do you know off the top of your head what rear end ratios were available stock for a '69 350/350?? The reason I am asking is because I am putting my thought into the best setup for my engine rebuild, cam selection, etc and wanted to know the rear gear for this purpose.

wfo76

69 350/350 factory combinations

M20 Wide Ratio - 3.36 std, 3.55 opt
M21 Close Ratio - 3.70 std, 4.11 opt

Check the tranny stamp on the right side, starts with letter P
and ends with an A for M20 or B for M21 (early 69's may not have the A or B).