Master cylinder options
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Joined: Aug 2024
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From: Massachusetts
Master cylinder options
I'm going to be installing C5 front calipers on my C4 using the Van Steel adapters, and I'm a little concerned about how much larger the piston area is compared to the C4 single-piston calipers. The C5 uses either a 1" or 1.1" master cylinder instead of the C4's 0.88" (7/8") bore. Are there any replacement options out there? Didn't see anything but the stock cylinder on Summit, but I don't know how they're determining compatibility.
I looked into just swapping in a C5 master cylinder, here's what I found: The C5 booster has 4 studs instead of 2 on the firewall side, so it would be difficult to swap the whole assembly. The master cylinder itself doesn't have the same hydraulic connections, and it doesn't have the integrated proportioning valve, but I can work around those differences. The only thing left, as far as I can tell, would be the booster-to-master-cylinder mount stud locations. I measured mine at 3.64" apart, does anybody know if the C5 is the same width? Anybody heard of this being done? I know the C5 brake swap is not uncommon, so there must be some info out there somewhere; have people just decided it isn't necessary to change the master cylinder?
I looked into just swapping in a C5 master cylinder, here's what I found: The C5 booster has 4 studs instead of 2 on the firewall side, so it would be difficult to swap the whole assembly. The master cylinder itself doesn't have the same hydraulic connections, and it doesn't have the integrated proportioning valve, but I can work around those differences. The only thing left, as far as I can tell, would be the booster-to-master-cylinder mount stud locations. I measured mine at 3.64" apart, does anybody know if the C5 is the same width? Anybody heard of this being done? I know the C5 brake swap is not uncommon, so there must be some info out there somewhere; have people just decided it isn't necessary to change the master cylinder?
Last edited by TylerScott; Dec 11, 2024 at 04:41 PM.
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I have C6 Z06 brakes at all 4 corners of my 85. The stock master cylinder is okay but I do plan on installing a 4th gen F-body master cylinder in the future. This thread shows one installed https://www.corvetteforum.com/forums...r-upgrade.html
Thread Starter
Advanced
Joined: Aug 2024
Posts: 78
Likes: 12
From: Massachusetts
I have C6 Z06 brakes at all 4 corners of my 85. The stock master cylinder is okay but I do plan on installing a 4th gen F-body master cylinder in the future. This thread shows one installed https://www.corvetteforum.com/forums...r-upgrade.html
