'67 J56 calipers

[Bill H.]

Re: '67 J56 calipers

Dan------


I would never, ever use any sort of racing pad for street applications, including those suitable for mild racing applications like autocross. Sometimes racing stuff is fine for the street but brake pads are not an example of such a case.

I agree with Joe 100%. Even the semi-metallic pads.

As for Hawk Brake Pads, I've used a ton of their products, mostly on racecars, but they make one of the best, street pads for C4's, their HPS pads (High Performance Street) are awesome.
That being said, I wouldn't buy Hawk J56 pads just because they fit, not without knowing the compound. The only way I would consider those pads is to contact Hawk directly and find out what the compound is and more importantly what the pad characteristics are.

http://www.hawkperformance.com/

[Kenneth B.]

Re: '67 J56 calipers

Dick-----


Yup, and that's exactly how GM did it. Any standard caliper can be easily converted to J-56. However, the converse cannot be accomplished----a J-56 caliper cannot be converted to standard.

Early 1967 with J-56 used the 1st design calipers and pistons. These pistons used the "thin" Pyroceram insulators.

Late 1967 with J-56 used 2nd design calipers and pistons. These pistons used the "thick" Pyroceram insulators.

JOE
Is there a reason that the center pin boss had to be milled off for J-56? was there a clearence problem. If not it would seem a wast of time.
KEN

[Wayne M.]

Re: '67 J56 calipers

....Is there a reason that the center pin boss had to be milled off for J-56? was there a clearence problem. If not it would seem a wast of time...

Ken -- clearance; " (J56) Brake shoe structural rigidity is increased by flanging the top of the shoe, and two pins are used to retain the shoe within the caliper assembly" -- from 1966 Corvette News.

You can see in the pics that it has to be shaved, or the horizontal part of the flange will hit the boss for the pin on regular calipers. Note the "holes" for the pins are oblong "slots".

Also, the standard brake pad shown, #5452513 is the 2nd issue, with real asbestos compound; [1st issue was bonded, not riveted]. The J56 pad is 1st issue #5468882, costing 4 times the price of standard. There was a subsequent J56 issue, #5470991, costing $148 list, in 1980 (for the two front calipers). Were these for the '73-5 Z07 option ?

[Kenneth B.]

Re: '67 J56 calipers

WAYNE
Thanks I went out & looked at mine & I see what you are saying. I have not had my Corvette up on a lift since I bought it back from the wife of a friend that died. I sold him the 435 25 years ago & we didn't pay that muck attension back then. I had forgotten it was a J-56 car till I looked at the tank sheet. I don't know what pads are on but they are duel pin.
KEN

[Robert K.]

Re: '67 J56 calipers

Hi Mike,

Yes, it was on the street. I came within a few inches of an accident one day (a long time ago) when I didn't know the characteristics of these pads. I had just left work and was headed home and had to make a sudden stop....Unfortunately, the stop was not sudden and the distance between automobiles closed quickly. I was able to avoid a crash.......The problem is that these pads require a extreme amount of force (they need to build up heat) to be effective and on the street with little to no braking the heat never builds up and the pads are not effective. Now, in high speed situations where the brakes are utilized much more, the situation is reversed. The pads heat up nicely and the brakes are fantastic. On the street, you want a pad that will "react" quickly to a minimal amount of pedal force and have high stopping characteristics -these pads are not designed for that use!