C5 master cylinders
Thread Starter
Burning Brakes
Joined: Dec 1999
Posts: 1,023
Likes: 1
From: New Carlisle, Ohio
C5 master cylinders
What year did they do away with the proportioning spring in the C5 master cylinder? I am wanting to install an external proportioning valve, and need a master cylinder with no internal proportioning. Thanks.
Le Mans Master
Joined: Apr 2001
Posts: 5,331
Likes: 39
Re: C5 master cylinders (gene284)
My 2000 C5 has an external proportioning valve with a brake bias spring in it.
My C5 does not have Active Handling, cars that do have AH have what GM calls a combination valve. both are just south of the master cylinder.
[Modified by Gary2KC5, 8:32 AM 9/26/2001]
My C5 does not have Active Handling, cars that do have AH have what GM calls a combination valve. both are just south of the master cylinder.
[Modified by Gary2KC5, 8:32 AM 9/26/2001]
Thread Starter
Burning Brakes
Joined: Dec 1999
Posts: 1,023
Likes: 1
From: New Carlisle, Ohio
Re: C5 master cylinders (Gary2KC5)
So at least in year 2000, a car like yours does not have any biasing within the master cylinder, correct? And, as I understand what you are saying, neither do those with active suspension. All biasing is done external of the master cylinder both with standard suspension, as well as active suspension? Do you know if this is true of earier C5's?
Thanks
Thanks
Advanced
Joined: Mar 2000
Posts: 96
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From: Orange County CA
Re: C5 master cylinders (gene284)
I believe the external porportioning valve / biasing spring was away with in 2001.
Here's a snippet from Joe Oldham's article form the Z06 specs (and I believe all 2001 C5s)...
Pressure Modulator
The original Bosch 5.0 hydraulic pressure modulator is replaced by an improved Bosch 5.3 modulator. It is reduced in size, transmits less noise, and works better at low temperatures. It weighs 3.5 pounds less than the previous modulator and provides better apply response at lower temperatures (minus 20° Celsius), meaning that the system will become fully functional more quickly after a cold startup.
Dynamic Rear Proportioning
The enhanced system has dynamic rear brake proportioning capability, electronically balancing rear brake pressure to prevent rear brake bias, or lockup. This new software feature eliminates the need for a rear brake circuit-proportioning valve, resulting in fewer assembly parts and fewer brake pipe connections. In addition, the master cylinder pressure sensor is now integrated into the new Bosch pressure modulator.
Here's a snippet from Joe Oldham's article form the Z06 specs (and I believe all 2001 C5s)...
Pressure Modulator
The original Bosch 5.0 hydraulic pressure modulator is replaced by an improved Bosch 5.3 modulator. It is reduced in size, transmits less noise, and works better at low temperatures. It weighs 3.5 pounds less than the previous modulator and provides better apply response at lower temperatures (minus 20° Celsius), meaning that the system will become fully functional more quickly after a cold startup.
Dynamic Rear Proportioning
The enhanced system has dynamic rear brake proportioning capability, electronically balancing rear brake pressure to prevent rear brake bias, or lockup. This new software feature eliminates the need for a rear brake circuit-proportioning valve, resulting in fewer assembly parts and fewer brake pipe connections. In addition, the master cylinder pressure sensor is now integrated into the new Bosch pressure modulator.
