i got a gut that will sell me a 9bolt with 3.42 posi, and rear discs. for 200 bux what ya think?

 

i would say that is a good price considering the gears, but you better make sure, 9 bolts NEVER came with 3.42s but they did come with 3.45s and those are fairly rare because they only came in 305 TPI cars with G92 option. Just make sure you are getting what you pay for, the 9 bolts are a strong rear end though, alot stronger than the 10 bolt.

 

maybe it was 3.45 i know is was 3.40 somthing. 9bolts came in IROC's right?

 

yeah, the car would be from an IROC with a 305 TPI

 

As the other guys said,the 3.45 only came in 305/5 speed cars.Which are hard to find.

 

My friend got one for $100 but it had the 2.77s in it.

 

I have a 1989 Iroc with a 5.7, it has a 9 bolt posi with disc, you're saying this isn't the original rear that came with it new?

 

NO,i am not saying that at all.My 350 GTA also has a 9 bolt with 3.27 gears.I am saying only 305/5 speed got the 3.45 gears.I have no doubt your IROC is a 9 bolt and most likely has the 3.27 also but the auto 305s and 350s didnt get the 3.45s.

 

Most available and common BW 9-bolt is the 2:77 which was the standard ratio with a 350 TPI Auto to 1989. The 3:27 was a option and again only on 350 cars. The 3:45 is the rare one because it was a option on only the 305 TPI 5sp cars. Short story a lot of 2:77 out there vs the other 9-bolt ratios.

 

Like other said make sure it is a 3.45 9bolt. I got mine for $250 complete from disc to disc. It was out of a 1989 305 5-speed formula.

 

another thing about the 9 bolt, 89 was the only year it had the PBR brakes. if you have a 9 bolt and want to upgrade to PBRs good luck finding the mounting plates. you could get the 3.45 borg rear and not have the G92 RPO. i have a 3.45 rear and dont have the G92 RPO. i have the 3.45 RPO in my sheet.