Using 9 bolt adapter plates on a 10 bolt
Thread Starter
Member
iTrader: (2)
Joined: Jan 2007
Posts: 149
Likes: 0
From: NewBrunswick, Canada
Car: 84 TA Black/ Gold
Engine: 383 With Vortec Heads
Transmission: 700 R4 Lvl2 Performabuilt 9.5 Vert
Axle/Gears: Moser 9" with 3.70
Using 9 bolt adapter plates on a 10 bolt
I have been reading for days and i can't seem to find the post. I thought i read somewhere of someone elongating the holes or something.Has anyone used 9 bolt adapter plates with pbr calipers and modifyied them to install the disc brakes on a 10 bolt. Was it successful and safe. Thanks for any info
Joined: Sep 2005
Posts: 27,918
Likes: 2,448
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
The answer depends on what backing plates you're starting out with.
If you have 9-bolt PBR backing plates, then you probably can mount them onto a 10-bolt with a minimum of effort. It's a little more hassle putting 10-bolt ones on a 9-bolt because the axle tube diameter, and consequently the main center hole in the backing plate, is slightly larger on the 10-bolt. The best way is to flip them over and use them on the opposite sides, which allows you to drill all-new holes, rather than elongating the ones that are there.
I can't imagine modifying 9-bolt Saginaw backing plates to hold PBR calipers to a 10-bolt.
If you have 9-bolt PBR backing plates, then you probably can mount them onto a 10-bolt with a minimum of effort. It's a little more hassle putting 10-bolt ones on a 9-bolt because the axle tube diameter, and consequently the main center hole in the backing plate, is slightly larger on the 10-bolt. The best way is to flip them over and use them on the opposite sides, which allows you to drill all-new holes, rather than elongating the ones that are there.
I can't imagine modifying 9-bolt Saginaw backing plates to hold PBR calipers to a 10-bolt.
Supreme Member
iTrader: (7)
Joined: Mar 2001
Posts: 6,420
Likes: 5
From: Fort Mill, SC, USA
Car: '88 Iroc, '91 RS, and a '70 RS
Engine: 5.7 TPI; 5.0 TBI; ZZ4/T56 on the ag
Transmission: A4, A4, slated to be a T56
I have a set of new 10 bolt plates I'll swap you straight over for, LMK. No need to modify a set of good plates when you can have the right parts.
Ed
Ed
Thread Starter
Member
iTrader: (2)
Joined: Jan 2007
Posts: 149
Likes: 0
From: NewBrunswick, Canada
Car: 84 TA Black/ Gold
Engine: 383 With Vortec Heads
Transmission: 700 R4 Lvl2 Performabuilt 9.5 Vert
Axle/Gears: Moser 9" with 3.70
Thanks for the replies and thanks for the offer ed, but I was just wondering about the mod because I was looking at a rear end for sale and this is what he did to install the disc system. Just wondering how reliable the mod would be . thanks
Joined: Sep 2005
Posts: 27,918
Likes: 2,448
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Well without seeing how it was done, it would be hard to guess at that. Could be carefully and thoughtfully done, or it could be a hack job. It's all in the details.
Joined: Aug 1999
Posts: 19,282
Likes: 103
From: Lawrence, KS
Car: Met. Silver 85 IROC/Sold
Engine: 350 HO Deluxe (350ci/330hp)
Transmission: T-5 (Non-WC)
Axle/Gears: Limited Slip 3.23's
Thread Starter
Member
iTrader: (2)
Joined: Jan 2007
Posts: 149
Likes: 0
From: NewBrunswick, Canada
Car: 84 TA Black/ Gold
Engine: 383 With Vortec Heads
Transmission: 700 R4 Lvl2 Performabuilt 9.5 Vert
Axle/Gears: Moser 9" with 3.70
I guess I am going to go with a 4th Gen Swap LS1 and I don't have to worry and I know what I have . Thanks folks 
Thread
Thread Starter
Forum
Replies
Last Post
morrow
Suspension and Chassis
78
Jan 13, 2024 12:29 PM
IROCZDAVE (88-L98)
Engine/Drivetrain/Suspension Parts for Sale
1
Nov 19, 2015 07:03 AM