1964 Brake Option

[Larry M.]

In 1964, what is the difference between the J56 and J65 brake options? Thanks....

[John H.]

Re: 1964 Brake Option

In 1964, what is the difference between the J56 and J65 brake options? Thanks....

Larry -

About $580.00 .

The short version is:

J65 was sintered metallic linings on the shoes, with finned drums.

J56 was a different type of metallic lining (Ceremetallix) on special shoes, with special ventilated finned drums, internal fans, ventilated heavy-duty backing plates, front backing plate air scoops, dual-outlet master cylinder, and vacuum booster; essentially the same brake system as the '63 Z06.

Others will add more gory detail.

[Michael H.]

Re: 1964 Brake Option

Larry,

I'm sure John meant to say J65 was sintered metallic linings on the shoes, without finned drums. Drums for J65 looked exactly the same as standard drums.

Only the Z06/J56 package drums had fins.

[Wayne M.]

Re: 1964 Brake Option

...I'm sure John meant to say J65 was sintered metallic linings on the shoes, without finned drums. Drums for J65 looked exactly the same as standard drums. .....

Here's the NOS J65 front shoes and interesting installation instructions on how to prepare the standard finish drums for use with the metallics.







y

[John H.]

Re: 1964 Brake Option

Larry,

I'm sure John meant to say J65 was sintered metallic linings on the shoes, without finned drums. Drums for J65 looked exactly the same as standard drums.

Only the Z06/J56 package drums had fins.

Michael -

Yup, fat-finger typo, and I can't edit it any more. The J65 drum (non-finned) was the same raw casting as the base drum, with a finer micro-finish on the friction surface.

[Michael H.]

Re: 1964 Brake Option

Michael -

The J65 drum (non-finned) was the same raw casting as the base drum, with a finer micro-finish on the friction surface.

...with a slightly thicker web section.

[John H.]

Re: 1964 Brake Option

...with a slightly thicker web section.

Yup - the drums were centrifugally-cast in rotating molds, with the webs loaded in the mold first; drums for the J65 application got thicker webs.

[Dan H.]

Re: 1964 Brake Option

My 64 J65 front drums have an 'X' and an 'R' stamped into the web piece. Also had a green brush mark, and a white brush mark on them. The rear only had an 'L' stamped into the web. All 64's with J65 had a booster as standard. My old 63 J65 front pull back springs were thicker than standard pull back springs, had a purple/reddish color.
Dan

[Wayne M.]

Re: 1964 Brake Option

...... drums for the J65 application got thicker webs.

Is there a spec on this ? Just measured one of the two Jan-Feb '64 rear drums I have [cast on edge W8____ 3828688] and get 0.108" thick on the web [assuming the web is the disc with the 5 wheel studs and the big center hole for the hub of the spindle].

Part of a complete rear suspension assy I bought years ago, just to get the pumpkin. They have regular linings but I don't know the past history -- was a 4.56 car so anything is possible .

[Michael H.]

Re: 1964 Brake Option

Is there a spec on this ? Just measured one of the two Jan-Feb '64 rear drums I have [cast on edge W8____ 3828688] and get 0.108" thick on the web [assuming the web is the disc with the 5 wheel studs and the big center hole for the hub of the spindle].

k:.

Wayne,

Yes, the web is the disc section of the drum that looks like a dinner plate. Measure the thickness between the 5 holes for the wheel studs.

Engineering specs for the standard drum call for .109-.119". Drum web for metallic brakes is .125-.135".

I should have mentioned that the different web thickness for metallic drums is only for front drums. The rear drum web thickness is the same for both standard and metallic shoes.