I have a 1960 buick invicta that needs a complete brake overhaul. I'll be changing the front 45 fin to 90 fin so that I can run other wheels. The only change here is the width of the 45 fin is 1/4 less than the 90 fin, so brake shoes will be a touch less in width. I removed the master cylinder for a rebuild. Its a Delco/Moraine unit with a 1 inch bore. I looked at the 1968 corvette dual master cylinder which looks like it will bolt right up to the booster. Now the catch for me is that the corvette MC is 1 1/8 bore. So the question is whether the difference in bore sizes will cause me a problem or concern. Is the fact that the booster has a 1 inch end on it vs 1 1/8 be an issue? Is there a pressure difference between the two MC's that should be a concern? Your comments will be appreciated. Thanks.
I'm not sure if this is an answer to my own question, but I did some more research and found that the 1970 Chevelle had a 1 inch bore. So at least that would match up. But the questions still stands if anyone wants to expand on the question. Thanks
I had a 60 olds and just redrilled the firewall to add a dual m/c with matching booster (not the one from the car) and a proprtioning valve to the rear just in case. then split the front brakes from the rear but left all 4 drums as is. Worked great.
Thanks PapaJohn.. I"m trying to avoid a redrill and brake shaft shortening/lengthening. That's why I thought I'd stick with the stock booster and get a different MC. There seem to be many choices out there. It's just a matter of finding one that works. My main concern remains regarding the bore match-up
I think the Corvette 1 1/8" master is best suited for 4 wheel disc brakes, calipers requiring more volume.
Don't use the Corvette MC on your drum brake application. Disc brake masters have a check valve in them so the pads do not go back into the caliper where-as drum brake shoes have springs that return the shoe back into the wheel cylinder. Most GM's have the same bolt flange so look for a dual master from a 68-70 Old, Buick, Cad, Impala W/O disc brakes. Pat
Go with a 67 or newer full size Buick (or chevy, or...like 1934 coupe said) M/C for Drum/Drum if you are keeping the drum brakes. It should bolt right up. Just make sure you get the Delco-Moraine so the push-rod is a match. Then you need to add a short line from the M/C to the line for the rear brakes and move the brake switch from the master to the hole that used to go to the rear brakes (unless yours is already mounted on the splitter). Have fun. More volume isn't the problem, it's the lower pressure that would be a problem.
This is precisely the advice I was looking for. This way I'll keep the drum brakes for now and have a dual master for safety. Thanks for the info gentleman...
The reply from Stevie was great. I'm trying to do this now to my 60 Electra BUT I have the non-Delco [can't think of the name] power brake booster. What should I do to get a dual pump master cylinder to work? What unit should I buy and what do I do with the push rods? Thanks, Guy
I've never seen any check valves in any disc brake masters, so if you can provide some proof of some you've seen or know of, I would really appreciate it.
the problem isnt the volume its the pressure inch and a eighth has more volume at lower pressure for disc brake set up on drum drum you need a 1 inch bore, less volume more pressure. for short extra volume not a good thing
Steve: Your message sounds great BUT those 67 master cylinders have 2 mounting bolts and the 60 Buick I have has 4 mounting bolts so how is that going to work with my booster? Furthermore, I do not have the Delco booster, its the other one which I forget the name of. please help me at [email protected] thanks, Guy
Email me and please let me know if you found a dual master cylinder that would work with your 4 bolt booster. Thanks Guy [email protected]
This would be a bad thing, wouldn't it? As I see it, a check valve would basically be a line-lock that you couldn't release.
in 1960 i think gm used a quite standard booster on most applications. if this is the case, then i think you should look into a MC from a 62-64or 65 year cadillac. i was told that the booster(1960) would accept a MC(62-65ish)and be a direct bolt on. cadillac had drums all around those year and also had a prop.valve. so that would be something to look into. what i will do with my 1960 convertible deville, is take a booster/mc combo from a 1968 deville. 68 had a 4 wheel drum setup but had no prop valve! booster runs 1200 psi....and i have never had a problem with them after owning 3 1968 cadillacs. i know you dont want to redrill, but when i done mines, i had to basically "bore" the existing holes very little, and add to small washer to line up the pedal assmebly for stud length. just an idea
STEVIE, I just dropped in on this thread by luck, "I Hope" Just so happens my MC on my 64 Buick Electra 225 just took a crap and I was wanting to upgrade to a Dual MC "IF" there was a simple straight forward swap. What is this "DELCO-MORAIN" all about. How do you ID it?? Is the difference the 2 bolt, 4 bolt thing?? My MC is a 2 bolt and of course I am sticking to brake/brake. I do not have the time to get into a major project of wrong rod length and Etc. Redoing short lines no problem and I believe the brake light switch is on the pedal. Any info would be greatly appreciated.
"EBBSSPEED", 1934 coupe is probably talking about a residual valve, not a check valve. A resid. valve allows a few pounds of pressure left in the system to do what he described. I have also seen mention of this resid. in some MCs.
Wow, this thread has had a bit of activity in the last 24 hours. There are two types of boosters on GM's, Delco-Moraine and...the other one (Bendix?...ZMAN, help me out here). The difference is the amount that the MC goes back into the hole in the booster. Take your single master to the parts store and match up that end. As for a four bolt MC, I didn't go back that far, but you might see if a late 60's Chrysler unit will fit. Their manual MC's are four bolt up into the 70's. Not sure on the power units. The other option is to install a later power booster. Your unit is likely over 50 years old now. This might be the perfect opportunity to kill two birds with one stone. Hope this helps, Stevie
Subscribed. I also want to see where this leads. I recently bought the wife a '62 Buick Electra and although it stops great with the original power brakes with the single MC, I plan on upgrading to a dual MC for safety's sake. After all it will be hauling G-kids too.
Check out a drum brake equipped Javelin. That's what I put in my Willys. I paid $34 for a new one on Ebay. Certainly cheap enough to experiment. Just make sure you bench bled it well.
WILLY! Are we talking 2bolt or 4bolt on the Jav? We got 2 or 3 posters of different interest going here. As for me I got a 2 bolt to match up to and Stevie has me headed for the finish line. Oh yeah NAPA gave me a price of app. $35.00 to replace the single original
Thanks Stevie. Thanks for the info. Looks like we got us a "CONVOY" of Buick fans. Will take my old orig. down with me. At least I know what to look for. Trying to stay away from any unnecessary work or expense at this time with boosters and all. Got the Buick up for sale, but may have it for awhile. Figure it would be a good upgrade. Might be a little bit till I fit the project into a godaddy mode, but I will return with the results. Thanks. CG
I have a 49 Buick which has the power brakes under the floor. I converted to a 8"universal unit with a hanging peddle I used a mc from a 68 full size Chevy with drum/drum application. Once I got it bled correctly it works great. TP
I assume that you have a 59 since its on your avatar, i am planning to do this swap on my 59 also. What kind of peddle did you use?