how strong are the 8.5 rears

[xtreme43s10]

hello i did a search and really couldn't find what i was looking for and was hoping some of you guys can help, i have an 8.5 rear with an aftermarket eaton posi, gears, and girdle, and need to do another gear swap for my new motor, but was wondering how strong are these rear ends ? are the stock axles good or would aftermarket be a beter choice if i wanted it to live ? i don t run at the track much it s mostly street driven, i know the big factor of weather or not it will live will be if i hook up, i would like ot run slicks in the future. also i have a t-56 tranny in there. any tips you guys can give me will help alot. ive been looking into doing a 9 inch swap but if the 8.5 will live then i ll leave it in there. with the new motor it will put down 450+ rwhp, and 550+ rwtq both numbers are very conservaive, but i don t plan to beat the motor and take it to it s limits for street duty. thanks again

 

[xtreme43s10]

no body has any clue or idea ?

 

[wagon]

I think Jack Cotton is still running his 8.5. He's in the 8s. I think you will want to change out the axles(30 spline, 31, whatever it takes), which requires changing out the posi. I think that is what spline they are. I haven't had to get one built yet, so I am not sure on the parts needed. So, I would defineatey check on it before you take my word for it.

Anyone else??

Brian

 

[mayosmechanic]

8.5 is stronger than most people realize.Many guys are in the 9's with them.Some run spools with after market axles others run aftermarket posi's.Jack is still running a 8.5 and has gone into the 8's.I personnally plan to run mine with a aftermarket posi and axles with a girdle.My car will make 700rwhp.HTH.