Brake Booster Question?

[Mudflat]

So I am taking this booster off a 1957 car. The front disc brakes are on seperate lines. The top and bottom one, coming out of valve in front, control left and right disc. I am putting it on a 1969 truck that I converted to disc brakes. The lines are factory on truck, front line splits. Should I run new and split and plumb like the 57 car or can I used factory and plug a hole on the valve?
Also the bolt pattern at fire wall doesnt match up. Should I cut top studs on truck and drill new ones to fit?

[special-K]

To use that proportioning valve you want to use all it's ports. Might want to consider something made for a C/10 that bolts on. If you are stuck on using that one then go with how it is designed. On mounting, I imagine you will need to make an adapter plate.

[LH Lead-Foot]

The rod on the booster has to line up with the brake pedal. On the 67C10, the hole is low and usually requires a linkage bracket for about $60. I don't know where the older booster rod lines up, but drilling new holes will take advantage of the OEM bolts that have some reinforcement so the bulkhead or firewall doesn't flex. Some brake pedals have a linkage hole higher up, use it if you have one. It helps with mechanical advantage for your foot to booster ratio. LoL.

The original front brake line work off of one feed line into a "Tee", then from there it goes to left & right. You have two lines for the front, so that 3/16" flare fitting will require union with a flare design. You can fabricate a bracket to hold them after you make a decision to go outside the frame or inside the frame. I chose to drill the frame and run a single front line thru a grommet for each side to hide them, but evenly spaced to look clean. Remember to leave enough room for wrenching when you make you run choice. I used a flare union in the middle of the frame and secured each line with wrap around clips bolted to the crossmember for the right and inside the frame for the left. The rear line can follow the fronts in the same fashion, while spaced equally to look good. A flare union is used there also to the rear single line. Hope this helps. Other choice is to plug one of the front lines at the proportioning valve, but use a flare fitting plug to complete a good seal. Then run one line down to OEM "TEE" fitting. I think the front lines on that proportioning valve is 3/16" and rear is 1/4". You have a couple of ways to go, depending on how much room you have to work in. You may have to get a 3/16" to 1/4" flare line adaptor if you use the OEM "TEE" with the lines shown in the photo. Best of luck.

[Andy4639]

Originally Posted by Mudflat

So I am taking this booster off a 1957 car. The front disc brakes are on seperate lines. The top and bottom one, coming out of valve in front, control left and right disc. I am putting it on a 1969 truck that I converted to disc brakes. The lines are factory on truck, front line splits. Should I run new and split and plumb like the 57 car or can I used factory and plug a hole on the valve?
Also the bolt pattern at fire wall doesnt match up. Should I cut top studs on truck and drill new ones to fit? Attachment 1809858

You will be way a head of the game if you buy a new 11" booster and master cylinder for your truck. I took one of those small boosters and swapped my 11" booster and hated it. The truck just didn't stop good at all. I ended up going back to the 11" booster.

[demian5]

Plug the top line of the combo valve and use the bottom fitting for the existing brake line. i know I had to get adapters to get the truck lines to work with my combo valve.

Get a bigger booster and make sure the bell crank for the booster is correct (as stated above).

[Mudflat]

I have this booster so I will try it first, amost identical setup on the 57 as on the 69 truck and it stopped it fine. The brake lines will have to be adapted to fit.