With all the mods I have done I've found myself with a bottle-neck. I would like to replace the gears in my 88 firebird with 4.11 gears. Is it possible? where can i buy them? for how much?

miles aka 88 427 camaro has 9 bolt parts, not sure what ratio gear sets there are to be had.

do you think 3.73 gears can work in the 9 bolt???

don't beleive 3:73 is a ratio for a 9 bolt

do a little research thier or talk to miles at 9bolt.com 3.73 is the spec ratio

3.73 would be the way to go. Problem is they are very expensive for the 9 Bolt Borg Warner Rears ($500 with installation kit). Does anyone know of another sourse besides www.9bolt.com???

If you're car still has the long runner tpi system, even with aftermarket runners and tb, you're not going to want to go over 3.73 gears. I have a brand new precision gear 3.70 ring a pinion set for a 9 bolt rear that I'll sell you for $300 and that's shipped to your door. That's about 25 dollars plus the cost of shipping ($20-35) cheaper than you'd buy them from a vendor. They're still in the box, unused.

i believe this place ahs them, it says 3.73s for GM 7.75, so im assuming it works for our rears... but they only have the gears it seems, no carriers or anything else.
hope this helps
not sure of the price form them.

edit: im a dork , i forgot the link...


www.ringpinion.com

Miles at 9bolt.com has or can order any available part for a 9 bolt rear. If you need a 3 series carrier (new or used) he can get them. Like all other vendors for 9 bolt parts his prices are expensive. 9 bolts parts have to imported from australia with the exception of bearing kits and us gear/strange and precision gear's 3.70 ring a pinion set. Due to the fact that select 85-90 f bodies are the only american car to ever have this rearend makes them very limited and in-turn outrageous prices. For all the info you'd ever want to know technically about a 9 bolt look here:
https://www.thirdgen.org/techbb2/sho...72#post1126172

Good Luck!

Drain, what do you mean by us gear/strange and precision gear's 3.70 ring a pinion set? Is there a less expensive route to go using 3.70 ring and pinion set? If yes, where can they be purchased?

Thanks

Sorry, didn't have a chance to read all the replies before I the previous reply.

Ede or Kevin should make my 9 bolt info post a sticky. It would save alot of people alot of typing and save server space.

Hey, Qs with the posi test, just to confirm. I'm I understanding your instructions right, car in park? (auto) lock one side of the wheel (Ill assume have a friend hold it) rotate the other (tork whench on one of the lugs?) sorry for the lame Qs but Im sure other wonder the same

Thanks again for the 9bolt info

That is how I found the directions on the net. I forget where, I've spent at least a 100+ hours scouring the net for info on these rears.
What I did one time was raise one side of the car and test the other. My posi tested fine. In hind site, I would have tested both sides that way just to make sure. I don't know if it makes any difference, but I do wonder about it from time to time. I'm getting ready to change gears and I'm going to test it again and shim the diff posi cones this time if necessary.
Good Luck!
draino