Another hydroboost question

[onebadd73]

getting ready to swap out my vacuum booster for a a Chevy Astro HB unit. I bought a 1980 corvette mc with the larger 1 1/8 bore. I have Chevy disc brakes up front and Lincoln rear disc brakes in the rear. My question is the proportioning valve? My bronco came with 4 wheel drum brakes, do I need to swap it out to a 4 wheel disc brake one or can I leave it alone with the HB?

Thanks

 

[thegreatjustino]

The point of a proportioning valve is to make sure the rear brakes don't lock up before the fronts. If you don't have this problem, don't worry about the valve. I've always been told that with four wheel discs, if you need a proportioning valve you should use an adjustable one and put it in the rear circuit. Use it to increase or decrease the pressure going to the rears as necessary to prevent premature lockup.

My $0.02. There are guys on this board much more knowledgeable about brake systems than I.

 

[POPPAWS BRONCO]

For the time and hassle and to not touch it twice I replaced mine when I did my Hydro boost conversion.


Hey!!! Let me hold a dollar I'm in the middle of a restore here!

 

[toddz69]

getting ready to swap out my vacuum booster for a a Chevy Astro HB unit. I bought a 1980 corvette mc with the larger 1 1/8 bore. I have Chevy disc brakes up front and Lincoln rear disc brakes in the rear. My question is the proportioning valve? My bronco came with 4 wheel drum brakes, do I need to swap it out to a 4 wheel disc brake one or can I leave it alone with the HB?

Thanks

The valve you currently have isn't a proportioning valve. It's a shuttle valve that moves a piston one way or another if a brake line fails so that the system doesn't totally fail. I removed mine when I did my disc brake conversion years ago but if I was doing it again, I'd probably leave it there.

I'd put an adjustable proportioning valve in the rear line.

Todd Z.

 

[onebadd73]

Got it, thank you..