Australian 9 bolts
12-17-2002, 10:37 AM
#1
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Australian 9 bolts
Just out of curiosity.......I've heard enough about 9 & 10 bolt rears and could literally have an ongoing war between the ya and na sayers as to which one is stronger. I understand they were only offered on 3rd gens from 87-89, my question is.....If the 9 bolt rears where really that good, then why were they discontinued? Just wondering cuz my 9 bolt is on its last leg and I need a new rear, and am currently tryin to figure out which way to go.
12-17-2002, 11:35 AM
#2
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If you knew enough to debate the pros and cons of both, you'd know why the 9-bolt is stronger and which way to go. The 9-bolt was installed on 3rd gens from 1985 to 1989. Due to cost (for GM), it was discontinued. It was imported from Australia ($$$), still used down there. It is the "equivalnet" to Aussies as the 10-bolt is to US.
12-17-2002, 12:15 PM
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12-17-2002, 02:55 PM
#4
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The 9-bolt is both stronger and more costly than the 10-bolt. it was used in the IROCs because GM was afraid the higher torque output of the TPI350 would break 10-bolts, but then they decided it wasn't worth the extra money to import the 9-bolts so they stopped using them.
Note that even during the 9-bolt years (85-89), GM put 10-bolts in cars with auto tranny 305's and all V6's (except the TTA).
Note that even during the 9-bolt years (85-89), GM put 10-bolts in cars with auto tranny 305's and all V6's (except the TTA).
12-17-2002, 03:31 PM
#5
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Originally posted by TheGreatJ
The 9-bolt is both stronger and more costly than the 10-bolt. it was used in the IROCs because GM was afraid the higher torque output of the TPI350 would break 10-bolts, but then they decided it wasn't worth the extra money to import the 9-bolts so they stopped using them.
Note that even during the 9-bolt years (85-89), GM put 10-bolts in cars with auto tranny 305's and all V6's (except the TTA).
The 9-bolt is both stronger and more costly than the 10-bolt. it was used in the IROCs because GM was afraid the higher torque output of the TPI350 would break 10-bolts, but then they decided it wasn't worth the extra money to import the 9-bolts so they stopped using them.
Note that even during the 9-bolt years (85-89), GM put 10-bolts in cars with auto tranny 305's and all V6's (except the TTA).
12-17-2002, 07:37 PM
#7
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You can get a used 9 bolt for about $350.
I sold mine for $200 and a set of extra T-Tops. I didn't realize I had the 9 bolt until my friend that I sold it to told me.
He wanted the posi unit and his friend wanted the gears. I told him it was a 10 bolt and that is what we assumed it was.
I'd go 9 bolt if I were you. Stronger than the 10 bolt and cheaper than the 12 bolt. You pay a little more for the gears though so get one with the gears you need already installed.
I sold mine for $200 and a set of extra T-Tops. I didn't realize I had the 9 bolt until my friend that I sold it to told me.
He wanted the posi unit and his friend wanted the gears. I told him it was a 10 bolt and that is what we assumed it was.
I'd go 9 bolt if I were you. Stronger than the 10 bolt and cheaper than the 12 bolt. You pay a little more for the gears though so get one with the gears you need already installed.
12-17-2002, 08:42 PM
#8
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...
Originally posted by aklim
AFAIK, it would be hard to purchase a 9 bolt right now. I'd go to a Ford 9 in custom made for our cars before I did that. 10 bolt is weaker than the 9 bolt, both of which are weaker than the Ford 9 in
AFAIK, it would be hard to purchase a 9 bolt right now. I'd go to a Ford 9 in custom made for our cars before I did that. 10 bolt is weaker than the 9 bolt, both of which are weaker than the Ford 9 in
gearhead knows your rear is only as strong as the parts you put inside of it. A built 10 bolt can handle the power. Ive seen 1200HP 
go through a 12bolt NUMEROUS times.. this car does wheelstands on the bumper and has never broke! IMO FORD 9s are overrated. Besides.. who wants FORD parts on their Chevy.. ICK! 
12-17-2002, 10:12 PM
#9
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Re: ...
Originally posted by OneSickS10
Everyone is so quick to jump and say FORD 9's are the strongest.. ok.. well they may be the easiest rear to swap gears in.. and have heavy duty parts.. but any TRUE gearhead knows your rear is only as strong as the parts you put inside of it. A built 10 bolt can handle the power.
Everyone is so quick to jump and say FORD 9's are the strongest.. ok.. well they may be the easiest rear to swap gears in.. and have heavy duty parts.. but any TRUE
gearhead knows your rear is only as strong as the parts you put inside of it. A built 10 bolt can handle the power.
12-17-2002, 11:57 PM
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Originally posted by aklim
AFAIK, it would be hard to purchase a 9 bolt right now. I'd go to a Ford 9 in custom made for our cars before I did that.
AFAIK, it would be hard to purchase a 9 bolt right now. I'd go to a Ford 9 in custom made for our cars before I did that.
Originally posted by aklim
10 bolt is weaker than the 9 bolt, both of which are weaker than the Ford 9 in
10 bolt is weaker than the 9 bolt, both of which are weaker than the Ford 9 in
12-18-2002, 09:09 PM
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hey greatj, u can have my busted oh-so-rare 3.45 9-bolt
I'll tell ya, this car hauled pretty good *** b4 it broke for a 16 year old car ('87 IROC, LB9, T-5, 3.45:1 rear [RPO code GM3]). However, I've yet to experince an '87 IROC with the L98, or any other 3rd gen L98 for that matter.
I'll tell ya, this car hauled pretty good *** b4 it broke for a 16 year old car ('87 IROC, LB9, T-5, 3.45:1 rear [RPO code GM3]). However, I've yet to experince an '87 IROC with the L98, or any other 3rd gen L98 for that matter.
12-19-2002, 06:50 PM
#13
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Hey Smoothie, exactly what is broken in there...the posi or the gears?
I picked up a 2.77 '89 9 bolt complete with the big brake setup for $100 to put in my Iroc. That's a deal IMO...the brakes alone were worth that. I then sold my '88 2.77 complete for $200, so you can expect those rears around that price, and they are pretty plentiful.
Ed
I picked up a 2.77 '89 9 bolt complete with the big brake setup for $100 to put in my Iroc. That's a deal IMO...the brakes alone were worth that. I then sold my '88 2.77 complete for $200, so you can expect those rears around that price, and they are pretty plentiful.
Ed
