Nascar 9" gears

[Ralph A Powell]

Originally Posted by Mark Ugrich

I have a set of 6.20 gears I installed recently. As far as I know most NASCAR gears are made by Gleason and new are in the $2000.00 range.Gleason only makes gears in 9310, which is the same as a pro gear.
There were no pinion depth markings or numbers to go by, so it took a little work to get them right.I got the depth close, then used the comet tail on the pinion to dial in the pattern.

Gleason figured out how to make 9310 gears live in NASCAR. They grind the gears as I understand it. GM bought the first 2 years of production so their teams had a exclusive for those 2 years.