c1 (1960) wheel cylinders

[Dan D.]

Re: c1 (1960) wheel cylinders

Check the wrench size for the bleeder screws. They may be metric (10mm) instead of 7/16. Mine were. No problem with that - just don't like it. -Dan-

[Jim L.]

Re: c1 (1960) wheel cylinders

Are the finned drums in your photo the same as Tom Parson modified drums from a later model chev?

Joe,

No they aren't. The drums Tom used are equivalent to NAPA 440-1248 drums which look like this:



In contrast, the drums I've used are NAPA 440-1575:



Both drums are for 2" brake shoes but both have friction surfaces which are substantially wider, making them good candidates for home grown big(ger) brake systems.

A key difference between the two drums is the offset of the friction surface relative to the mounting plane.

If you look carefully at the two photos you can see that the 440-1248 drum locates the friction surface more inboard (by, oh, .15" or so) than does the 440-1575 drum. Tom had to compensate for this by putting the drum in a press and altering the offset. (I believe he may also have put his drum in a lathe and trimmed the inboard flange to visually expose the tips of the fins.)

The 440-1575 drum has the same offset as the stock C1 drums.

Jim

[Joe M.]

Re: c1 (1960) wheel cylinders

Great information!

With a change in drums and 2 1/4" shoes, do any other components need to be changed to ensure the brake system works as intended?

Is the wheel cylinder diameter critical? 1 1/8 and 1 3/16 will both work?

Thanks Jim
Joe

[Jim L.]

Re: c1 (1960) wheel cylinders

With a change in drums and 2 1/4" shoes, do any other components need to be changed to ensure the brake system works as intended?

On my Big(ger) Brake system, the web of the brake shoes is offset from the center of the width of the friction surface by 1/8" in the inboard direction. It is this way so the wheel cylinder push rods align properly with the web of the shoe.

I accomplished this by having some 2-1/2" shoes modified at a machine shop. The shop trimmed 1/4" from whatever edge I identified as the "inboard" edge of that particular shoe.



F*rd and L**coln have both used 2-1/4 shoes in 11" applications, so I suppose one could simply put some of these on in place of the original 2" shoes. I wasn't sure about the angularity of that push rod, though, and that's why I went to the trouble to modify some 2-1/2" shoes.

Is the wheel cylinder diameter critical? 1 1/8 and 1 3/16 will both work?

Either will work and I've had both sizes on my '60. I prefer the 1-3/16 cylinders because they result in lower pedal effort. Pedal travel is slightly greater, though.

Jim