Originally Posted by us7race
With my 8.5 10-bolt (stock caps and cover) I have only broken 1 set of gears and that was right at the end of this past season.
My 60' are 1.32-1.36 at 2865lbs. I wouldn't be worried at this time. JMO.
It has more to do with weight and torque, what works on a 2500lb vehicle wont last for $hit in a 3800lb vehicle, plus there wasnt a bigblock made from the factory that didnt have the bigger 12 bolt carrier.
My buddies has a 71 nova, 496BBC he's broke countless 8.5 gear sets, and he has the billet caps, studs, aluminum cover, after market axles the whole nine yards. He was finally convinced to upgrade to a 12 bolt after the last set only lasted 3 weekends.
But on the flip side - I have a buddy who has a fully narrowed 8.5 ten bolt in his tube chassis 68 firebird w/ 427 sbc that runs 5.90's all day long w/ short times in the low 1.30's, he's never had a moments trouble out of it, not that I would have done it but its just an example.
I think yours will be fine at your Hp level and weight, when your money gets right > stick a DANA 60 in there and forget about it.
Goodluck, Cp