Im working on my 49 Chevy Fleetline. I have read many threads about replacing the factory single reservoir m c with a dual reservoir m c from a late 60s to early 70s car or truck , fabbing a bracket and lines. Which is a lot cheaper than buying a new original replacement. My questions are , does the dual reservoir make a difference over the single reservoir ? Is this really worth doing to save some cash . I just hate to do this and then say i should have just left it stock . I am leaving this 49 (for now) anyway a all drum car . Do you need to put a porportioning valve in line when using a dual reservoir m c ? Also is there anyone out there that may have specs on the wheel cylinder bores. Im not talking about the specs in the shop manual . I know that the clearence between the bores and the aluminum piston should be .002- .004 ths. Im wanting to know the tolerance allowed for the rubber seal itself. If i can remove a couple thousands to clean up my bores and finish hone i may end up .005-.007 over the aluminum piston size. Thats not a problem , i can machine up a couple pistons in no time. I would like to think that the rubber seals are pretty forgiven ? Dont know so i thought i would ask here. Thanks for any help . Im wanting to get this on the road soon and the brakes is the only thing holding me back .
Would think you wouldn't need a proportioning valve as you have one circuit to the front and one to the back. Don't you usually use a p-valve when doing the conversion on disc/drum set up?
I would agree with not needing a proportioning valve with drum drum. The advantage is, you have a back up in case something happens. Your call on wether to keep a juice jar or upgrade.
A lot of guys do the upgrade to the dual master cylinder as a safety item. It's true, that if you lose a brake hose on a single system, you're likely to have to throw out an anchor or stick your foot out the door to get stopped. I've thought about doing this upgrade, but my single system works well, and the "parking brake" term didn't apply back then, it was called an "emerbency brake" and would get you stopped in the event of a failure. All that being said, if you decide to change to a dual system, you should be good to go as long as the master cyl. you get was designed for drum/drum application.
The '49 probably still has Huck brakes if it's stock. Each shoe is individually hinged and not self engergizing like Bendix brakes. If you want to stay with the drums it would be a good move to change to '51 stock brakes. I had a '50 in 1958 that had the Huck brakes and they were a constant pita.
Im not familiar with the Huck brakes , mine are mounted to what i would call a sissor type bracket and the wheel cylinder pushes the them out at the top . I thought this was standard? But im learning here , thanks for the update on the later brakes . I may need to do that not sure what i have .
The brakes changed from huck to self energizing bendix in 51. The backing plates and spacers from a 51-54 chevy front end can be bolted on to 49 and 50s. Not only does this bolt on upgrade give you significantly better brakes, but the parts are also cheeeper and more readily available at your local parts hut. I made this change on my 50, never drove on the hucks. 14k miles later i have never once felt unsafe, ever. Even made it through rush hour traffic on lakeshore drive in chicago. I also added an aftermarket under the floor dual master cylinder. 53 backing plate with bendix getting ready to go on.... Its upside down in the pic....
Very nice and i thank you , i will look for some used backing plates and spacers asap. I havent spent $ yet and now im glad . I see the difference now . Hey if anyone has these parts send me a meesage please, i hope im not out of line asking that on this thread if so im sorry.
Hmmmmmms my 50 master cylinder had a hole in it for the clutch pedal/linkage...I'd think if you awapped a master cylinder, you'd need to re fab up some clutch linkage. I rebuilt my old 50 master cylinder and had zero problems with it...kept my '50 clutch pedal and fab'd up some new linkage when I switched to a smallblock/4 speed setup.
Glad I dropped in on this thread! I've been reading about "huck brakes" for a while, but never got a good explanation and/or pics about what the deal was ...although I had my suspicions. Thanks to the pics in this thread, my suspicions were proven correct. If your expertise is based on vintage motorcycle lore (as is mine), what we're talkin' about here is the difference between single leading shoe brakes versus twin leading shoe brakes.
Ha, ha! Lake Shore Drive in a '50 Chevy. That brings back memories. In about 1962 my gf (later wife) and I went to her junior college dance at the Edgewater Beach Hotel (long since torn down) that was at the north end of LSD. Poor b/4 picture attached. Later that night the '50 tried to drift it's way back downhill to the parking garage because that car hiker didn't know that the parking brake cables weren't attached. Traded that car and her Nova convertible in on a GTO in 1965. The Chevy resold before the Nova off the dealer's lot.
^ Ya, i went up to visit a friend who lives on the north side, so no matter what, i gotta fight through the whole town to get there. That time got into town at dusk, there was a concert at soldier field.... It was a complete mess. Even with out the bumper to bumper. Id try to leave 5-6 car lengths in front of me and the next car.... Whatever dude, in chicago thats just an open invitation to everyone in the other lane to cut in front of you. My legs were shaking when i finally got where i was going. But the fiddy and i made it. As for the original topic..... When you get the new parts, be sure to get the spacers. You must have the spacers. Its best to get everything just to be sure. Try putting an advert on craigslist asking for the front end off a 51-54 that someone has lying around after doing a mustang II swap. Most folks will be happy to give you a deal on the parts, since they are under the impression they are junk, and want the crap outta the garage. If you can get the complete front end, just take it. These front ends come on and off with just a few bolts. That way if you wanna lower it at some point, youll already have uprights and spindles you can send off to have chopped.
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