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al cid
08-29-2019, 05:16 AM
trying to convert 56 bel air 6 cyl to dual master cylinder brakes. car has 4 wheel drums, manual brakes. trouble locating master cylinder that will give clearance with oil filter canister. help! thanks

Rick_L
08-29-2019, 06:31 AM
What is the application for the master cylinder you tried? The master cylinder for a 67-67 Camaro, Nova, or Chevelle is the one usually used and it's also the shortest in length compared to other possible choices. I'm not familiar with the placement of the oil filter on a 55-57 though. Would it be possible to move it?

al cid
08-29-2019, 10:20 AM
What is the application for the master cylinder you tried? The master cylinder for a 67-67 Camaro, Nova, or Chevelle is the one usually used and it's also the shortest in length compared to other possible choices. I'm not familiar with the placement of the oil filter on a 55-57 though. Would it be possible to move it?

i don't think it can be moved due to air cleaner mounting on other side of exhaust manifold. as to the using of a 67 mc, who sells the older style. most are wider than original 67 mc. tried a kit from eckler's. not only was the mc to wide, touching oil filter canister, but none of the supplied lines to the proportioning valve came close to fitting. extremely disappointed in eckler's. they sent the wrong master cylinder and could not send or did not want to be bothered. frustrated

chevynut
08-29-2019, 12:11 PM
Welcome to the site. A pic might help.

scorpion1110
08-29-2019, 05:11 PM
i don't think it can be moved due to air cleaner mounting on other side of exhaust manifold. as to the using of a 67 mc, who sells the older style. most are wider than original 67 mc. tried a kit from eckler's. not only was the mc to wide, touching oil filter canister, but none of the supplied lines to the proportioning valve came close to fitting. extremely disappointed in eckler's. they sent the wrong master cylinder and could not send or did not want to be bothered. frustrated

Yeah, I ordered their kit for power drum brakes. Threw away the Prop valve first. First one leaked as did number two so went with a Wilwood prop valve. Then I threw away the lines as they looked horrible coming up the firewall. Bent my own. So now I have the booster and the Chevelle MC. Pretty sure the Booster is bad, brakes are rock hard. Still checking but expect that to go in the trash next (finish is lousy anyway). So all that will be left is my $380 Chevelle MC (cost of the kit).

Probably will just use Wilwood stuff and convert the drums to disks (as soon as I find a zero offset kit, the offset being why I kept the drums).

Honestly it would have been easier just to set the $380 on fire. Id be in roughly the same spot and would have space in my trash for all the future repop stuff I buy that wont fit or wont work.

Scorp

Custer55
08-30-2019, 06:35 AM
A Wilwood master may be a bit thinner than the Chevelle master and the lines can be attached to either side. If you have manual brakes you would need a 7/8" dia. master. With drum brakes you would need to add 10 lb. residual valves to the front and rear brake lines. If and when you would convert to disc brakes you just remove the 10 lb. valves as you don't need a residual valve with disc brakes unless the master is below the calipers which it would not be on a tri-five. The Wilwood adjustable proportioning valve would be a good idea also. I have a Wilwood master and prop valve on mine with 4 wheel disc brakes (C4 Corvette) and it works well. (1" master with a small 7" booster.)
Brian

Gmvette
09-04-2019, 09:31 AM
You might want to consider power brakes as they greatly aid the drums. I added power to the drum brakes in my disc delete brake 65 corvette.

I mounted power booster flush on the firewall to keep compact. Having disc/drum 57 w/small power booster has a corvette m/c with residual valve for rear brakes. Very pleased with the outcome and performance.