Do I need a proportioning valve if i'm running a 73 Chevy master to a front D60 and 14-bolt rear?
I think I should have one for the front.

Is it the 1/2 ton master? Is it rear disk? What booster?

In most cases, the proportioning valve is needed to restrict fluid pressure to the rear axle if it has drum brakes while diverting more presure to the front with disks. The wheel cylinder on a drum brake has a much smaller volume capacity than a caliper piston. If you're running disks front and rear you wont need it. Be aware that some boosters have the valve built into them, (where the rear line goes into the booster) if this is the case, it can be pulled out with a sheet metal screw and a pair of pliars.

SloToy is debating the same thing and I think he decided to go with a Wilwood prop valve. I heard they're about 30 bones.

Originally posted by mudtruck44
Is it the 1/2 ton master? Is it rear disk? What booster?

It's a Toyota 1985 booster-73 3/4 ton master- front D60 -and rear disks from a front D60 on thew 14-bolt.

since you've got the gm master maybe a gm product that came stock with front/rear discs would work best.
New trucks (02 and maybe 01 have 4 wheel disc) and corvettes...
trial and error, just dont tail gate

im having a front 44 and rear 60 with discs and i pulled a camaro booster,vette master and prop valve. im gonna see how this works. unless anyone has any reason as to why it wouldnt?

Vova, do you the brakes hooked up yet. I was just wondering how the pedal felt. If it feels too soft, a prop. valve can help. With those big calipers, I would want a bigger master though. I have the same set up except 1/2 ton rear calipers and a 1 ton 4 wheel disk master. It works good but now my power booster is too small. I am going hydro-boost though.

I guess my brakes work pretty well though, 2nd at TTC in braking.:D

A proportioning valve is used on the rear brakes.

Stock, a proportioning valve is part of the Combination Valve on GM trucks. Many run with the stock combination valve after a rear disc swap. Using the stock drums will need an additional proportioning valve as the K30 had a load height sensing valve under the bed.

Also a residual pressure valve can be mounted in the rear brake output of the mastercylinder. AFAIK GMs don't use a residual valve, instead they use a metering valve (on the front line) as part of the combination valve. Rear disc don't need either, as there purpose is to allow take-up of the slack on the rear shoes (but it shouldn't hurt). ;)

Who sells the Wilwood valve? Who has the best deal?