Master cylinder upgrade

[joeg]

Hi All,

Well I finally finished my frame off that took me 5 years to do. She saw her first sunlight on Saturday, so I took her out on her maiden voyage around the block. As I aproached the second stop sign the brake pedal went to the floor, HOLY S***. I was close to home so I was lucky there was no traffic. I weened her home and the rear caliper was bleeding badly. I removed the caliper and removed the leaking cup seal and behold! yep it was installed backwards. Its amazing the crap you buy today!! So I said to myself, self this aint gonna happen to me again, so my question is to you guys, is their a kit to install a dual master on a 66?? That is, a kit with all parts needed and with minimal rework of what is??
Thanks in advance.
Joe

[Geek's 65]

Eckler's has the brake line kit so all you need is a master cylinder from a 67.

[Marlar]

Geek

What about a power booster? From what you said, I can get a '67 master cylinder and power booster for a '67 and some '67 dual brake lines, etc, and I am good to go with that stuff on my '65?

[Geek's 65]

Originally Posted by Marlar

Geek

What about a power booster? From what you said, I can get a '67 master cylinder and power booster for a '67 and some '67 dual brake lines, etc, and I am good to go with that stuff on my '65?

I didn't have power brakes before so I didn't add them. Mine are still manual. I have heard (there are so many others here smarter than me that can verify this) that the 67 master cylinder is the same one for both manual and power brakes. So I would think that you could add the booster and get power brakes pretty easy. But I can't say that for certain.

geek

[JohnZ]

If you get the correct '67 master cylinder (casting #5455509, stamped "DC" at the front, with the "deep-hole" rear piston), you can use it for either manual or power brakes; '67 was the only year that manual and power used exactly the same master cylinder.

[Marlar]

Originally Posted by JohnZ

If you get the correct '67 master cylinder (casting #5455509, stamped "DC" at the front, with the "deep-hole" rear piston), you can use it for either manual or power brakes; '67 was the only year that manual and power used exactly the same master cylinder.

John Z

My primary source for parts for my '65 is aftermarket Vette catalog outfits. What do I look for or ask for? Call and ask for casting number 5455509? Am I correct in assuming that it will fit the vac booster and that the pair will bolt up to the firewall correctly?

[Geek's 65]

Try this link http://www.cssbinc.com/index.asp?Pag...S&Category=316

Corvette Stainles Steel Brake. They have a kit and I am sure you can ask them all about using the power booster.

Geek

[JohnZ]

Originally Posted by Marlar

John Z

My primary source for parts for my '65 is aftermarket Vette catalog outfits. What do I look for or ask for? Call and ask for casting number 5455509? Am I correct in assuming that it will fit the vac booster and that the pair will bolt up to the firewall correctly?

As Geek noted, CSSB has the new reproduction 509 master cylinder, and line kits for the conversion. When you talk to them, see if you'll need a different booster-to-master cylinder pushrod; most power brake master cylinders (except '67) have a shallow-hole rear piston and use a "short" pushrod, but the '67 master cylinder with the "deep-hole" rear piston uses the "long" pushrod with a booster.

[Marlar]

Geek/John Z

Thanks for the info. I will follow up. Not being a "purist", I was thinking of a vac assist + '67 master cylinder in all chrome. You see I was "chrome deprived" as a kid and I am now catching up!

Am I correct in concluding that the piece that needs a long rod could be used as long as I can find the longer part? And that that part is the rod for a '67?

[JohnZ]

Originally Posted by Marlar

Am I correct in concluding that the piece that needs a long rod could be used as long as I can find the longer part? And that that part is the rod for a '67?

Yup, that's correct.

[rohard]

I had mine (65 Big Block Roadster) converted with a Kit number DB 503 from Zip Products (www.zip-corvette.com). It came with all required parts. Cost was $295.95 for the full kit. Included new dual master cylinder, brake blocks, proportioning valve, and brake lines to attach to existing system. Paid 4 hours labor to have it installed. Mechanic said everything was there that was need to convert from single to dual. (Mine was w/o power brakes, but made no difference when I ordered.) I feel a heck of a lot more secure driving a fixed caliper system prone to leaks with a dual master, but would lose NCRS points if I ever had it judged. Saftey is more important to me.

[Marlar]

Thanks guys. I quickly checked the Zip site and they may not offer the kit any longer. I will check elsewhere also.

[rohard]

Originally Posted by Marlar

Thanks guys. I quickly checked the Zip site and they may not offer the kit any longer. I will check elsewhere also.

Just checked, it is still offered. (Price has gone up.)
http://www.zip-products.com/Zip/prod...C8DC59A2A6D863

[Marlar]

All the info has been helpful in educating me. I have been told by a parts house that the proportioning valve is not necessary unless I want to upgrade to a '67 system. In other words it is said to work OK without the proportining vave. Does that sound plausible? I did want to go to a '67 dual master cylinder with vacuum assist. I understand that the vacuum can come off the back manifold or from the carburator(?).

[JohnZ]

No Corvette used a proportioning valve until the mid-70's - the device below the master cylinder on a '67 is simply a distribution block, and all it contains is the differential pressure warning switch - you don't need it. There's a tapped hole in your intake right behind the carb for a vacuum fitting - all the vendors have vacuum fittings for the power brake hose to the booster.