Brake Booster Guidance Needed

[EdSevered]

Hello all,
I am the third owner of a 71 Cheyenne 1/2T (avatar) with factory manual disc/drum brakes. Not knowing the truck's history, there are certain things that I feel like I should get new and completely replace, such as brakes.

I am in the process of collecting parts to redo the disc brakes and I'd like to install a brake booster with new master cylinder and proportioning valve. I have already purchased rotors and loaded calipers from R1 Concepts, and the Timken bearing kits. Next I am looking at getting hoses and the booster. Will redo the drums on the rear shortly.

As Brake boosters come in a variety of sizes: 7", 9", 11", etc., can I assume that the smaller the size the less "boost" assistance will be provided by the unit? If I plan on keeping a mostly stock vehicle, maybe a little lowering later, what is the smallest size I should I consider? Are there any other things that need to be considered?

Any recommendations on brand and/or place to purchase would also be appreciated.

TIA!
-Ed

[Sloan66]

I used my existing master cylinder, which I rebuilt, my existing proportional value. I purchased OEM booster from a junk yard off a 71 and used it for a core. It gave me all the needed brackets. I think the OE is 11 inch. I bought a rebuilt one from O'Reilly's, worked great no issues

[davepl]

Just get a reman unit from any auto parts store. It's about a $20 core if you don't have your old one. Master is cheap too. The expensive part is the prop valve, if you want it to look anywhere near stock, they're something like $250.

[EdSevered]

Thanks for the input guys, but I suppose I should get more to the point.

I am in the process of completely re-doing the brakes with new parts, starting at the front. I am going to buy a new brake booster w/MC and prop valve (disc/drum). I understand that the 11" booster is the size that would've been stock.

But, if I want to use a smaller size booster to keep the appearance a little cleaner under the hood, will there be any mechanical or safety issues?

Any recommendations on minimum size, brand, source, etc.?

Thanks again!
-Ed

[jmorri34]

Originally Posted by EdSevered

Thanks for the input guys, but I suppose I should get more to the point.

I am in the process of completely re-doing the brakes with new parts, starting at the front. I am going to buy a new brake booster w/MC and prop valve (disc/drum). I understand that the 11" booster is the size that would've been stock.

But, if I want to use a smaller size booster to keep the appearance a little cleaner under the hood, will there be any mechanical or safety issues?

Any recommendations on minimum size, brand, source, etc.?

Thanks again!
-Ed

I just did the exact same thing, new from the pedal to the wheels. Do yourself a favor and go to whoever you wanna use and buy a complete master/booster/prop valve setup for disc/drum or whatever you are doing. its around 250 or so for all of it. Its easier and all the parts are there and brand new. I personally got mine from CPP but anywhere with one of the vendors on here is fine as well and they are on our board. BE AWARE that you can get a bad booster right out of the box from anyone even the parts store. I did and chased it for a month and it was a bad booster from the beginning. Good luck!

[davepl]

If you are looking for a much smaller booster without sacrificing assist, then the easiest option is a dual-diaphragm unit. Packs twice the assist into a smaller package.

There's also the hydroboost option, which is pricier but also tiny.

[EdSevered]

Originally Posted by davepl

If you are looking for a much smaller booster without sacrificing assist, then the easiest option is a dual-diaphragm unit. Packs twice the assist into a smaller package.

THANK YOU! Two-words, that was all the information that I needed. I often marvel that simply knowing the right terms can open a whole new line of understanding. While I had seen dual-diaphragm boosters I had no idea as to the significance of that. Research has just become that much easier.

Thanks again, I hope I can repay the favor some day.

-Ed

[EdSevered]

Hello again,
I am in the collecting parts phase, preparing for several different jobs at the same time.

I read in another power brake booster related thread that there may be some pedal related part(s) that I'll need to get to complete the conversion from manual to power brakes in my '71 c-10 1/2T. I already have a mc, booster, prop valve (disc/drum), with bracket assembly. And rotors, calipers, seals, hoses. Can anyone clarify?

Thanks in advance,
-Ed