Master Cylinder upgrade

[Hairdoo]

I am looking to go with a Wilwood master cylinder for manual brake upgrade on my 72 2wd 1/2 ton, I talked to Wilwood and they need some info I dont have because my truck is 2 hrs away and cant check myself. The brakes are disc/drum and all stock. Does anyone know what the caliper piston size would be, rear wheel cylinder size and brake pedal ratio? Or has anyone done this and have a part # to go by?

[demian5]

Id just go with an early 70s corvette manual master cylinder and use your existing combo valve.

[BCOWANWHEELS]

Cant beat stock in any way unless you just want to spend alot for purdy looks

[mike16]

actually a corvette might not work , I think it has something to do with it being a dual disk set up in vettes while his is a stock disc/ drum st up.

Pontiac in the early 70's made a master cylinder for firebirds that was a disc/ drum MC set up for standard brakes. I have used the 72 firebird as the reference when ordering them in the past. nice thing is that many of the various brake lines are repro'd too so visually speaking it can be made to look very clean and simple install

its a common enough MC because its often the mc of choice for conversions too.

[Bigdav160]

Is there something wrong with the stock MC in this application?

[Keith Seymore]

I don't have the caliper size and rear wheel cylinder diameter in front of me, but I have the following:

Stock MC part numbers:

Delco - 5469574
Bendix - 6264985

MC bore diameter - 1.125 in

Pedal ratio - 5.9:1

K

[Keith Seymore]

Caliper piston diameter is 2.94 inches; rear wheel cylinder diameter is 1 inch.

K

[NC_John]

I put a wilwood master with their front discs on my 70. Ignore everyone saying "whats wrong with stock?" I have no power assist on mine and they feel fantastic. Great upgrade. Much better feel and performance over the 50 year old factory parts.

[Willie Makeit]

Originally Posted by mike16

actually a corvette might not work , I think it has something to do with it being a dual disk set up in vettes while his is a stock disc/ drum st up.

Pontiac in the early 70's made a master cylinder for firebirds that was a disc/ drum MC set up for standard brakes. I have used the 72 firebird as the reference when ordering them in the past. nice thing is that many of the various brake lines are repro'd too so visually speaking it can be made to look very clean and simple install

its a common enough MC because its often the mc of choice for conversions too.

been running Vette MC's on disc/drum setups for ages. the difference is in the prop valve, not the MC when it comes to the pressures being adjusted.