Dual master/ residual valve ?

[tb56]

For my 1956 Chevy 1/2 ton - drum brakes F&R.
Will I need to install a residual valve and distribution block when installing a frame mount non power dual master cylinder?


Any recommendation on remote reservoirs?

Thanks

[Old Buzzard]

Answered on the other board???

[BamaNomad]

AS RickL answered... need residual valves on both cylinders. GM masters had the residual pressure valves at the outlet of the lines on the MC...

[Rick_L]

GM masters had the residual pressure valves at the outlet of the lines on the MC...

Yes but most "rebuilt" master cylinders don't include them any more. Nor do new aftermarket units.

[BamaNomad]

Are residual valves of various pressure points available in parts stores? Do they "fit" the original GM MC as did the originals?

[Rick_L]

No, unless they stock the Wilwood style aftermarket ones, which are installed in line and are available in 2 psi and 10 psi versions. Most auto supplies won't have any kind of residual valve in stock. You can get the original style "duck bill" residual valves in a "rebuild kit" at rockauto.com for a late 60s master cylinder that came with them.

You need 10 psi valves for drum brakes. You need 2 psi valves for disc brakes on frame mounted master cylinders that are below the caliper bleeder.

Also a factory style disc/drum combination valve will have a residual valve in the outlet for the rear brakes.

[BamaNomad]

So rebuild kits are the only source for the 'original type' residual valves... Good thing to know.. Thanks!

[tb56]

Thanks for the information. Is a 1 inch bore master cyl. over a 1-1/8" a better way to go with drum brakes?

[Rick_L]

Yes, drum brakes came with a 1" bore master cylinder. A 1-1/8" bore mc will cause you to have to push harder on the pedal for a given stopping force.

[tb56]

Thanks for the info.