1939 Buick Special interchangeable brakes

[MarkL]

Is the front brake backplate from my ‘39 special interchangeable with the mid-fifties large series backplate? Do the mounting bolts line-up. ? I would like to swap in the larger 2 1/4 wide brake shoes? Thanks for any help!

[Wm Steed]

I have been told that the brakes from a 38 and later Century will fit a 38 and later Special.

I believe that you have to use the Century drums..

I have a complete set of 40 Century brakes.

Another option is to use '51 + Roadmaster brakes on the front, As I recall the 51 series 60 has 2.5 inch wide shoes. The backing plates step back over the spindle hub which allows the use of the wider shoes and drums, A side bar to this modification is that the later model finned aluminum drums will fit on the stock early spindles.. I have of set of the '51 roadmaster brakes that I was going to use on my '40 Buick Super.. Wm

[nat]

On 4/30/2024 at 12:39 AM, MarkL said:

Is the front brake backplate from my ‘39 special interchangeable with the mid-fifties large series backplate? Do the mounting bolts line-up. ? I would like to swap in the larger 2 1/4 wide brake shoes?

     I think you'll find that the wheel cylinder bore for the wider shoes is larger than than that used with the narrow ones.  If so, using the small bore cylinders will apply fewer pounds per square inch of force and might not improve braking.  Using larger cylinder bores with the same master cylinder will require more pedal travel which likely would only be a problem if the front shoes were adjusted way too loose.

     The front brakes do the majority of work but too much can make a vehicle nose dive and lose some needed control of the rear.   

     I'm not saying that any of this is a problem in this case but it might be food for thought.

Nat