power master cylinder

[Gary 38683]

What is the correct #for 1967 power brakes master cylinder. The vendor says that
#5455509 is for no power but I have been told that it is correct. Is there a
modification that has to be done? Getting lots of different answers here. HELP

[John H.]

Re: power master cylinder

Gary -

The vendor is confused - 5455509 was used for both power (J-50) and manual cars; the 346 was used only on J-56 H.D. Brakes.

[Rob A.]

Re: power master cylinder

THE MASTER CYLINDER ON MY CAR, WITH J50 POWER BRAKES, HAS CASTING#5460346. IT IS THE ORIGINAL, FACTORY INSTALLED UNIT. I GUESS, AS ALWAYS, THERE ARE EXCEPTIONS.

[Joe L.]

Re: power master cylinder

Rob-----

That's the first '346' I've ever heard of on a J-50 1967. It surprises me, too. For an item like a major brake component, I would not think that the factory could have gotten deviation authority very easily from Chevrolet Engineering. The '346' is a 1-1/8" bore master cylinder; the '509' is a 1" bore. For 1968 and up, 1-1/8" bore master cylinders were used for ALL power brake Corvette apps. But, that was for 1968+ and not 1967.

[John H.]

Re: power master cylinder

Rob -

That falls into the category of "possible, but highly improbable", and, in any event, is incorrect to both Engineering and judging specifications.

P.S. - Please turn off your "Caps Lock" key - standard internet protocol says caps are considered to be shouting, and it makes the post harder to read