Dave64

If I use the '67 dual MC on my power brake '64, where would I have to go from 3/16" to 1/4" lines? Of course, I just finished installing new brake lines on the frame last week. I've read that the rear distribution block would need to be changed, indicating the line from the mc would be 1/4". How much and/or where would I HAVE to use 1/4" lines? Fortunately, I've still got the bare frame in the garage, so I figure now would be the time to spend MORE money preparing for the conversion. Would the change effect the size of the front brake lines?

Thanks for any help.

Dave

toddalin

Why would you need to change out the lines? Just get the adapters to change the fitting size. I run a dual M/C on my '64 and never changed the hard lines except that I added a proportioning valve, residual valve, and line lock.

JohnZ

If you're staying with drum brakes, you don't want to use a '67 Corvette master cylinder - it's for disc brakes, and neither outlet has RPV's (residual pressure valves), which are required for drum brakes to avoid excessive pedal travel. You need a dual master cylinder for a drum/drum brake car (like a '67 Camaro, Nova, etc.).

jjtoma

John,

Is the bolt pattern(Camaro, Nova) the same for a 64' vette?

Found casting # 5452310 for drum brakes?

Thanks

Jim

JohnZ

The bolt pattern is pretty much standard. I'm not familiar with the casting #'s for drum brake master cylinders offhand; NAPA will have the Nova/Camaro drum/drum master cylinder.

Dave64

Thanks for the info guys. As I'm staying with drums (for the time-being), I'll use the Camero MC.

Dave

Great Swimmer

Dave,

I am doing the same swap. I've read these posts and am glad you asked the question.
Do you know if the '67 Camaro dual MC has the proportioning valve internal to the master cylinder? I'm trying to figure out all of the pieces/parts that go with this operation and I'm not sure what all I need beyond just the '67 Camaro dual mc.

Please let me know what you've learned.

Thanks,

Steve
678-481-1087

JohnZ

There are no master cylinders with internal proportioning valves, and Corvettes prior to '77 don't use external proportioning valves (except J-56).

For that conversion you want a '67 Camaro or Nova DRUM/DRUM master cylinder (so it has the residual pressure valves in the outlets behind the tube seats).

BAmacker

I installed a '67 MC/booster on my '63 11 years ago with no proportioning valve and have had great luck with it. The pedal is high and hard as a rock, stops like a million bucks, no leakage from the wheel cylinders or anything regarding the lack of a residual check valve. I did open a front and rear bleeder on installation and verify one circuit of the brakes was still functional.

The front outlet of the MC has a reducing adapter and feeds the front wheels. The rear outlet of the MC goes directly to the rear wheels, I probably have good pictures if you need them. I did have to notch the hood slightly to clear the MC, I did this by grafting in a small section of a '67 hood which has the appropriate clearance designed into it.

My car stops like it has 4 wheel disc brakes- really excellent! I've had other '63 owners drive it and they are amazed with how the brakes feel. IIRC, the brake components are all Muskegon brake- shoes, cylinders, hoses, etc, all 12+ years old, but under 15K miles. I don't run the car hard enough to need disc brakes- just cruise to shows and etc. I feel disc brakes would only be needed in a road racing application or other hard use. Most cruisers don't need them.

Good Luck!

lib

If you install one of the above 1967 MC's on a 63 (w/out PB booster) do you still need to modify hood? If yes, is there a MC that does clear?

buns

If you're not using a booster, you won't have to modify your hood. The booster added length to the master cylinder, and then they tilted it up, probably to clear the valve cover.




My '66 with booster. Standard master cylinder is not tilted up.

Great Swimmer

Regarding the parts needed for the '64 single cylinder master cylinder swap, I am going to answer my own question with info that I learned from a brake tech at YearOne.

1) No residual pressure valve is needed as long as the brake cyliners are lower than the brake master cyliner (they certainly are).
2) No proportioning valve is necessary. The "proportioning" is done by adjusting the rear brakes to "come in" (pads make contact with drums) before the fronts.

So, to do the swap, all you need is the '67 Camaro (for instance) drum/drum master cylinder. Run the front cylinder line to a 2-way splitter that goes to the front brakes, run the rear cylinder to the line that goes to the rear (that is already split once is gets to the back of the car), bleed the brakes and adjust the brake cylinders and you're done.

ccsbinc.com makes a kit that includes a MC that works, along with all new lines and stuff that they even say is not necessary for $290. The link is below.
http://www.cssbinc.com/1963-64corvet...brakecars.aspx

But the '67 MC with the hookups described above should be all that is necessary according to one smart guy (an ACE brake technician as well as an old car mechanic and parts guy).

Thanks for everybody's help.

toddalin

1) No, you still may need residual valve(s). If they are built into the M/C (most probably), great. If not, you end up giving the brakes an initial pump to pressurize the wheel cylinders before getting to the real braking action. When I used a '70s Corvette M/C on my '64 (with rear drums), the M/C had a 2# residual valve built in (as they do), and it was not enough for the drums and I always had to give the brakes a pump before they would work well.

2) While no proportioning valve may be necessary, it is the physical size of the brakes that do the "proportioning" and not the adjustment of the pads. If memory serves, the rears are 2-1/2" and the fronts are 3" providing more stopping power in the front. But while you are at it, you may want to add a proportioning valve anyway to better balance (fine tune) the system.

Dave64

Steve,

These guys gave you much more and better information than I could. Thank you guys for your technical expertise.

Dave

vette*1963

Picked up the master cyl and booster from Classic Prerformance Products on ebay for $110.

JohnZ

That information from Year One is a perfect example of "techs" who obviously have no clue how brake systems operate or how they're designed, giving out incorrect (and potentially dangerous) advice; both of those pieces of advice are 100% wrong, and could get somebody killed.

VITIV Coupe

I would like to convert my single power master cylinder drum/drum brakes in my 64 coupe to the duel master cylinder setup. I looked on the napa site and all I saw were 1' bore sizes and not 7/8 like my single master cylinder. Does anyone have the correct napa part number for my application for a duel master cylinder. I see they have more than a couple examples and I want to make sure I order the correct one.
Thanks in advance,
Leo