Power disk conversion question

[kknip]

What would happen if you did not change the manual 4 wheel drum porportion valve when you installed disk with a booster?Would it grab the front brakes too hard or possably lock up the back?

[FORDification]

The drum brake piece isn't a proportioning valve, it's simply a distribution block, and using one in a disc-brake system will cause your rear brakes to lock up prematurely. Don't do it. Use the right pieces, please....for the sake of the other folks on the road at least.

[kknip]

Thanks Keith,I wasn't sure,I will change it out as soon as I visit the pull a part junk yard to get one.Will it have the switch for the brake light on the dash?

[FORDification]

Yes it will!

[Wes]

Also if you can lower the brake booster apply rod 3/4-1" on the pedal, if going from manual to power brakes. manual brake have more mechanical advantage designed into them.

[fordman]

wes are you saying to move the brake rod attaching hole on the brake pedal arm. and that there is a diference in the power brake pedal hole postion as to the manual brake pedal arm hole postion.

[Wes]

Yes with power brakes you don't need as much mechanical advantage to get the same applied pressure. A lot of classic and antique disc brake conv kits are not power, and the vendor discourage adding power booster. I have done 2 disc conv 1 on a Chevelle which I lowered the rod, and 1 on a mini truck which I didn't they both seem to work fine. I am putting a hydro boost on my 67 f250, and having to make a custom rod, trying an angled booster bracket
1st which should but the rod at 3/4" lower the original.
I know some folks are running big tires and need all the help they can get, so the original spot may work fine. I guess I should have really said make the rod 90 degrees to the booster and not worry so much about mechanical advantage.