67 Big Brake....

[dennisinmaryland]

I am looking for a way to detect the big brake option on the 67 vette. Also, what are the benefits and distinguishing dimensions of a big brake car?

 

[WayneC]

Perhaps you mean J56 heavy-duty brakes?

http://corvetteactioncenter.com/specs/l88/l88prod.html

It would be on a big-block car with power brakes, and there are 2 devices below and slightly outboard of the master cylinder... one is a "distributor/safety switch" and is rectangular, the second is an adjustable proportioning valve that has a round body with a slightly smaller cylindrical knob-like adjustment snout sticking out of the front (overall length about 4 inches) that sits below and slightly inboard of the other device. A brake line connects the two.

Where a standard brake caliper has only one sliding pin near the top center that passes thru the pads, J56 calipers use two.

 

[JohnZ]

A '67 J-56 car will also have a casting #5480346 master cylinder with "PG" stamped on the semi-circular machined area at the front (all others use a 5455509 "DC"). The front calipers are the same production castings - they just have the center pin bosses machined off, and have holes drilled at both ends for the dual pad retaining pins; rear caliper castings are the same as production. The pistons are different, and have phenolic insulators attached to the pad end with one screw (to act as heat insulators between the pad plates and the pistons). The Kelsey-Hayes adjustable proportioning valves are worth a fortune.

 

[dennisinmaryland]

big brake info

Thanks to JohnZ and WayneC for the info...I've been out of my last vette (67 327/350 Marlboro maroon coupe) for over 8 years, but the bug is back and I'm homing in on a big block, big brake coupe. Can't wait and hope to get it real soon. Just joined this group forum and it seems like it's worth it already. Thanks again, guys.

 

[67HEAVEN]

dennisinmaryland,

Welcome to Let us know when the big day arrives.

 

[dennisinmaryland]

67 big brake car

Hey, thanks 67heaven...I sure will let you all know when the day comes. BTW, I really enjoyed your website. Although I am a "purist" by nature, your site has some excellent info regarding restoration good for any mid-year guy. I'm looking forward to future chapters on your site.