Rear Drum to z28 disk swap easy but dumb question
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From: Kissimmee, FL
Car: 1991 Camaro RS
Engine: 357cid
Transmission: T5 Swap
Axle/Gears: 10bolt 7.5" 3.23 soon to be 3.73
Rear Drum to z28 disk swap easy but dumb question
I have both cars sitting at my shop. I just need to know if i need to take the Rear disk proportioning valve, or if my drum one is fine..
im 90% sure i should take the disk valve but just thought id ask
btw my car is a 91 and the donor rear disk car is an 87 does that matter??
im 90% sure i should take the disk valve but just thought id ask
btw my car is a 91 and the donor rear disk car is an 87 does that matter??
Last edited by Saigon_Bob; Oct 3, 2007 at 07:42 PM.
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Re: Rear Drum to z28 disk swap easy but dumb question
You're putting in the crappy Saginaw disc brakes that don't ever work.
So you'll need to change out both the master cyl and the prop valve in order to complete the downgrade.
While the PBR calipers have hydraulic requirements sufficiently similar to drums tha tthe factory didn't see a need to use 2 different hydraulic systems to drive them (drums are the same as PBR discs), the same is not true of the Saginaw system. It needs its own hydraulics in order to fail to work right. Otherwise, it might keep the fronts from working right as well. Which would be bad, when the rears don't work.
So you'll need to change out both the master cyl and the prop valve in order to complete the downgrade.
While the PBR calipers have hydraulic requirements sufficiently similar to drums tha tthe factory didn't see a need to use 2 different hydraulic systems to drive them (drums are the same as PBR discs), the same is not true of the Saginaw system. It needs its own hydraulics in order to fail to work right. Otherwise, it might keep the fronts from working right as well. Which would be bad, when the rears don't work.
Re: Rear Drum to z28 disk swap easy but dumb question
does this mean that a car with PBR discs will have the same master cylinder and prop valve as a car with drums??
Thread Starter
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iTrader: (2)
Joined: Mar 2004
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From: Kissimmee, FL
Car: 1991 Camaro RS
Engine: 357cid
Transmission: T5 Swap
Axle/Gears: 10bolt 7.5" 3.23 soon to be 3.73
Re: Rear Drum to z28 disk swap easy but dumb question
You're putting in the crappy Saginaw disc brakes that don't ever work.
So you'll need to change out both the master cyl and the prop valve in order to complete the downgrade.
While the PBR calipers have hydraulic requirements sufficiently similar to drums tha tthe factory didn't see a need to use 2 different hydraulic systems to drive them (drums are the same as PBR discs), the same is not true of the Saginaw system. It needs its own hydraulics in order to fail to work right. Otherwise, it might keep the fronts from working right as well. Which would be bad, when the rears don't work.
So you'll need to change out both the master cyl and the prop valve in order to complete the downgrade.
While the PBR calipers have hydraulic requirements sufficiently similar to drums tha tthe factory didn't see a need to use 2 different hydraulic systems to drive them (drums are the same as PBR discs), the same is not true of the Saginaw system. It needs its own hydraulics in order to fail to work right. Otherwise, it might keep the fronts from working right as well. Which would be bad, when the rears don't work.
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Car: '88 Iroc, '91 RS, and a '70 RS
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