I have a 10 bolt rear in my 68 - it has been upgraded to richmond 373's before I got it but I am told its an open differential, what will it take to change it over to a posi unit?

 

basically you will be gutting it because you need to buy a posi carrier and if you are in there anyway, you might want to replace all the bearings and seals anyway. you will need to buy a 3 series carrier to go with the gears you want.

the cost of a good carrier alone can cost over $500.00 plus labor and new bearings.

chances are if you have an open rearend, you most likely have one of the 7.5" or 8.2" versions anyway which is a weak rearend to invest in. you might be better off looking through want-ads and trying to find an 8.5" one already built. if you can actually find one that someone hasn't taken out of the car yet you will be better off because you can hear how it sounds.

 

how can I tell if its a 7.5 vs 8.2?

 

i dont know about first gens but i have an 8.5" in my 79 and its got an open diff.

 

I think 1st gen 10 bolts were 8.2. 8.5 were 2nd gen much stronger but are a bit wider meaning you need to make some changes. The ideal would be a 12 bolt from a first gen, I think novas from that year are the same. They are stronger than either of the 10 bolts.

 

2nd gen Novas actually share the same suspension geometry as the 1st gen Camaro. 12 bolt rearends are WAY overpriced and unless you are putting 600+ rearwheel HP down constantly, with slicks, they aren't needed. even still, a 10 bolt can put up with 11 second times for a good life before it blows

 

Were the second gen novas (I messed up) an 8.2 or a 8.5?

 

I will say yes but I wouldn't bet my bottom dollar on that. I hate to say stuff definitely without info to back it up

 

sorry I tried to change the statement but I dont type that fast. My point is if he is going to spend the money to beef up an 8.2 rear he (In my opinon) might try to find a 12 bolt that fits that year I believe the 8.5 rear was put into the 2nd gen camaro and it it of a different dimention.

 

I hear ya on that speed typing thing

I have a 8.5" in my 69 and I've been backing up a very torquey 396 with a 3:73 rear for 7 years now an dhaven't had a problem yet. I also have a stud girdle on it too though

as far as the 12 bolt thing goes, it is almost cheaper to build a 9" for cheaper these days and those are tons stronger.