Looking for a decent, original drum brake proportioning valve for 67 442-

thanks-

Dave

 

I may have one, if it will stop raining I will check.

Johnny

PS I can't find what I think you are looking for, I must have thrown it away.

 

Drum brake cars do not have a proportioning valve; they simply use a junction block to connect the lines together.

 

I have several

Larry
lemoldsnut@aol.com

 

^^^THIS!

The distribution block has a differential pressure switch, which is simply a piston that slides one way or the other and trips a switch if you lose pressure in one side of the system. This makes the BRAKE light on the dash come on - usually right as your foot goes all the way to the floor.

More to the point, even factory 1967 A-body DISK brake cars do not use a proportioning valve. They use a metering valve that delays application of the front brakes slightly to allow the rear drums to take up all the slack in the actuating links before the front disks start to apply. This is NOT a proportioning valve. The prop valve changes the ratio of pressures between the front and back brakes. The 67 full size disk brake cars DID use a prop valve in addition to the metering valve. The A-body cars did not use a prop valve until the 1971 model year.

 

pm sent

 

Joe,

What is the difference between this and a residual pressure valve?




.

 

Both are spring loaded check valves, but with flow restrictions in opposite directions. The residual pressure valve holds pressure in the line between the valve and the wheel cylinders. The metering valve holds pressure in the line between the valve and the M/C.

 

You guys are great! thanks for all of the info, Ill contact my friend and confirm exactly what he's looking for and get back-

Thanks-again

Dave

 

The 67 distribution valve/block is available new. I think I got mine from The Right Stuff. No need to buy used when a new unit is available.