I have a 91 firebird it has a rear end from a 89 forumla it has 273 gears and limited slip and I was wonting to step up to 373s a buddy of mine said that I could only go up to 308 is this true

 

yea they use different carriers i think theres some adapter to go to 3 series from a 2 series but from what ive heard the time and money to get the adapter thing to work your better of just buying a 3 series rear end

 

So does that mean that I will need a new rear end as well

 

yea imo just try to find one of the factory 3.73s might take a while but in the long run will be cheaper and much easier swap. you can Google 2 series carrier with 3 series gears to try to see what you need to do, ive never done it just heard my friend complain about it for ever when he did it lol

 

Ok so I need to find a carrier and gears and i should be set is that right

 

im not 100% sure if u can swap the carrier into the Axel or if you need an adapeter to do it thats why im saying check google

 

Ok thanks for the info

 

i have 3.73 gears in my rear end,the housing is stock 91 firebird with some brake components from an 87ta, there was no real problem but a little research wont hurt...good luck

 

From the ratios you discuss, I'm assuming you have a 10-bolt. The following may be helpful:

https://www.thirdgen.org/forums/tran...-10-bolts.html

JamesC