ok so a friend of mine has a used rear end out of a 91 firebird i believe with 28 spline axles and the 342 gears and is offering to sell it to me for 150 bucks, is it worth the time and money to swap into my car? i currently have a stock rear end in my 87 lb9 and i planned on wanting to upgrade the gears and was wondering if i should just go this route instead? and from wut ive read most prefer a 342 gear instead of a 373 correct me if im wrong?

 

Depending on your intensions the 3.42 is a great compromise in overall performance if you don't mind the little extra rpm at speed 3.73s are great... its in the neighborhood of 200-250 rpm difference between the two. My vote is 3.73

 

Yes, but there's more to consider. Since the 91 will be a 10-bolt check the following link for info on combination valve, parking brakes cables, and speedo gears:

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

JamesC