hello guys, how is the best way to tell what gear ratio i have in my 12 bolt rear on my 66 chevelle. one person said to rotate my rear tires one complete revolution and see how many times the driveshaft rotates and divide them, but with one revolution of my tires, my driveshaft turns only about 1.4 turns...that wouldnt be right....?any ideas?...thanks!

maybe because you don't have a posi in the rearend, the driveshaft will only spin that much. I think the better way would be to put car in neutral, mark the tire somewhere and spin the driveshaft to make the tire turn a complete revolution. Or better yet, take off the cover and make marks on a pinion tooth and ring gear tooth, and count how much teeth each has. Divide ring gear teeth by pinion teeth and you get the ratio. Example: 41 ring gear/ 10 pinion = 4.10.


Jay

Find the numbers stamped on the axle, and go here http://www.chevellestuff.com/generic/quick_decode_links.htm Click on RPO codes

Thanks! Seems I Have 3.08 Rear Gears! Thanks Guys For Your Help!