Conversion to Power Brakes
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Joined: Apr 2009
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From: Columbus GA
Conversion to Power Brakes
I am converting my 69 Coupe from Standard Brakes to Power Brakes. I have purchased a new PB Master cylinder and Brake Booster. Do I have to do any modifications to attach the Booster to the firewall and the Brake pedal. I have heard of doing something with an attachment point on the pedal itself. Any one done this before?
Burning Brakes
Joined: Jun 2003
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From: San Antonio TX
I am converting my 69 Coupe from Standard Brakes to Power Brakes. I have purchased a new PB Master cylinder and Brake Booster. Do I have to do any modifications to attach the Booster to the firewall and the Brake pedal. I have heard of doing something with an attachment point on the pedal itself. Any one done this before?
KO
Race Director
Joined: Dec 1999
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From: Forked River NJ
The firewall for the standard and the power brakes are different. It can be done but requires more than just a bolt on. I went to try this a few years ago and evetually went the Hydroboost way also. Much better braking than the vacuum assist anyway. More room also, that big vacuum booster takes way to much room. Look into the hydroboost system.
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Joined: Apr 2009
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From: Columbus GA
Power Brake Conversion
With this Hydroboost, what Master Cylinder do you use? I already have a new PB MC. There is a local shop that has a template for the hole that needs to be cut in firewall,but, it looks like there would need to be some mods to the metal plate on the inside of the firewall as well. I really do hate this car!
Burning Brakes
Joined: Nov 2006
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2022 C3 of the Year Finalist - Modified
You will need to take out the two screws that hold the master cylinder,
Drill two more holes for the booster, enlarge the center hole, and if I remember you need one short brake line.
I bought the conversion kit from Corvette Central few years ago.
Avner
Drill two more holes for the booster, enlarge the center hole, and if I remember you need one short brake line.
I bought the conversion kit from Corvette Central few years ago.
Avner
Instructor
Joined: Sep 2007
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Power on left and manual on right
You also need to make a new hole for the pushrod, and move the pushrod to the lower hole on the brake pedal. You will also need a new brake switch actuator bracket.
The kits are probably the way to go.
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Joined: Apr 2009
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From: Columbus GA
Avner, Would you go higher with the two new holes or lower? It seems if you went any higher, there may be a clearance issue with the Booster and the hood. The two lower bolts are going into a welded nut on inside of firewall, any lower there and you would miss the metal backing plate...and there is soooo much room to work in under that dash. Luckily mine is gutted right now, can't imagine doing this with a complete interior.
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Burning Brakes
Joined: Nov 2006
Posts: 954
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2022 C3 of the Year Finalist - Modified
To take the studs out just hammer them in, the head of the stud seat in a cage.
I used the two holes from the studs I took out and drilled new two holes under (I think).
take mesurment on the booster from the two low screws to the top of booster and mesured the destance from the stude on FW to the fender chanel height and see if you can close the hood.
On the new booster you have 4 screws so you need 4 nuts from the inside of FW, there are no welded nut on inside of firewall.
About the brake pedal & switch I don't remember that I change something.
I'm sorry but I did it ~8 years ago and didn't take any pic's.
you can see here the height of the booster after the change.
Avner
I used the two holes from the studs I took out and drilled new two holes under (I think).
take mesurment on the booster from the two low screws to the top of booster and mesured the destance from the stude on FW to the fender chanel height and see if you can close the hood.
On the new booster you have 4 screws so you need 4 nuts from the inside of FW, there are no welded nut on inside of firewall.
About the brake pedal & switch I don't remember that I change something.
I'm sorry but I did it ~8 years ago and didn't take any pic's.
you can see here the height of the booster after the change.
Avner
