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Master cylinders, push rods for same for use with manual 4 wheel disc brakes

Dusty Dude

Well-Known Member
Local time
4:14 AM
Feb 13, 2023
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Our '69 Coronet 500 acquired a four wheel power disc brake conversion sometime in it's life which I would like to change to manual operation. The new 496" engine will not generate enough vacuum to properly operate the booster so I would just as soon get rid of it. Besides it sticks out into the engine bay and bugs the hell out of me anyway.
My questions are what master cylinder and what push rod do I need to make the change. I understand that a MC with a 15/16" or 1" bore is the preferred size to avoid a hard pedal. Also is there a stiffener plate that goes between the firewall and the MC that I will have to come up with? I have found a left port dual chamber MC with built in residual valves on line that says it's for four wheel disc setup but I could not find any info on the bore diameter. Not looking for high dollar fancy stuff just good sound parts that work as they should.
Any guidance would be greatly appreciated.
Just need a manual brake pushrod or an aftermarket adjustable brake pushrod. Mancini, doctor Diff, and others sell adjustable ones
Thanks 4mulas. I appreciate the info.
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