bence13_33

How hard is it to switch from power brakes to manual brakes. I plan on running a solid roller with around .700" which means stud girdle time and I have a pair of Comp Cams polymer valve covers that I'd like to put to use but I need to ditch the power brake booster to do so. Is it as easy as buying a manual brake master cylinder and bolting it up or is there more to it? Any help/advice is appreciated. Also I'm not sure how well the power brakes will work with my planned cam of 272/278 duration @ .050" (something tells me it won't work good at all ;) ). Thanks in advance.

427V8

It's a little more complicated.

The power booster has 4 bolts the manual master only two, and of course they are in different places.

You need to change the push rod to a manual version.

You need to switch the push rod to the lower pedal hole, which means you need to get a new brake light switch bracket.

master power brakes has a power to manual brake conversion kit with a '69 masterclyinder, an adaptor plate and a new pushrod.

The switch bracket you need to get from Zip ( or make your own )

GrandSportC3

Don't know about a conversion.. but I don't think that it's complicated... I have manual brakes on my '68 and they work great!!!

That setup that you mentioned sounds really badazz!! I'm sure that it'll be well above 700 HP.. maybe even in the 800 HP range :cool:

bence13_33

Thanks for the information, it sounds a little harder than I expected but none-the-less still do-able. I'll probably end up going this route (for some reasons I have visions of this project being a PITA but oh well). Thanks again.

ram82fire

You might want to consider installing a hydroboost unit if you have power steering . It will give you ample clearance for your intended mods .

geo

Gordonm

:iagree: The Hydroboost gives a lot of clearance. I had manual brakes and then went to the Hydroboost. Never go back. In a panic situation the manuals are tough to control and stop good. With a big block tha tonly gets worse. It costs a little more than going manual but well worth it. I had someone else drive the car and they were impressed with the feel and stopping power of the system.

matchframe

:iagree:

Go with the hydraboost!

Power brakes without having to worry about vacuum.

www.bigdogvettes.com


[Modified by matchframe, 6:58 AM 4/15/2004]

LemansBlue68

I just did the opposite. I went from manual brakes to power. You'll have to raise the position of the master cylinder. You'll insert bolts through the firewall in the top most holes that your brake booster currently uses. The new M/C will attach directly to the firewall using those bolts. You may want to fabricate a plate to cover the existing hole that the brake booster currently covers and you may have to cut a new hole for the pushrod to pass through the firewall. Also the manual brake master cylinders use a 1" bore instead of the 1 1/8" that the power brake M/C uses. You'll also want to raise the position of the pushrod to the higher position (closer to the pivot) on the brake pedal. You'll also have to get brake lines for the manual setup that go between the M/C and the proportioning valve. Not a terribly difficult job.

With the kind of power numbers your motor is gonna be making I'd go with the others suggestions and use a hydraboost set up or vacuum pump and resevoir and keep your current booster.