I have a 1966 Cutlass with a single master cylinder and I would like to convert it to a dual reservoir. Is there a parts supplier that sells a kit to make the changeover or at least a list of the parts needed to do the job?

 

If you want to convert to a dual chamber master cylinder I suggest getting an OE one off of a later model Cutlass. I'm not sure what parts you would need though. Master cylinder, vacuum booster and proportioning valve at the least.

 

It's not quite that easy. The pushrod between the booster and M/C is longer on the single circuit master cylinders and won't work if you try to simply bolt a 1967 M/C to a 1966 booster. Yes, you can swap the combined 1967 booster and M/C onto a 66 and avoid this problem, but again be aware that the 1964-66 booster is 9" and the 67-up booster is 11". This is why 1967 442s used a single notched valve cover on the driver's side. It's not an issue on a small block car. I'll also add that there is no proportioning valve used on the four wheel drum cars, just a distribution block that really only serves to house the differential pressure switch that illuminated the BRAKE light if you have a leak.

I like to use the 1962-66 Cadillac master cylinder, which is dual circuit but configured for the long pushrod on these cars. It bolts directly to the original booster with no mods required. RAYBESTOS MC36373, about $71 at RockAuto.

 

If manual drum brakes, here is the original 1967 setup:

 

I appreciate your responses and I'll look into it more. The car is 4 wheel drum with power brakes.

 

Thanks for the explanation Joe.👍

 

When you use a 67 manual dual master to replace a single manual master on a 66 442, will a 67 line complete the hook up? Does anyone sell the complete conversion kit?

 

Unless you are changing the power booster you can't use a 67 master cylinder on a 66. Go back and read post #3.

 

The 66 does not have power brakes so #3 is not applicable regarding my line or complete conversion question.

 

Then you're fine. A brake line kit for a 1967 with manual drum brakes will work, assuming you install the factory distribution block in the stock location.

 

Thanks. The 66 distribution block is in the factory location. Does a 67 use the same distribution block in the same location?

 

No, which is why I mentioned it.

 

i agree try to go oem bought a kit for my 64 from inline unfortunatly i let it sit for a year before installing,no warr got lucky the rod was the adjustable clevis the lines and block were difficult the masrer cylinder lid gasket was too big and wouldn't seal an old gm lid worked better i still carry brake fluid very disappointed