Better Rear Brakes?

[Robert Simpson]

Thanks everyone for the help. Jim, yes the car is driven allot on the street. It is not really that fast mid to high 13's. But he can only bring it up to 2k on the converter to cut a light. It has the original small engine in it (307). I was thinking about the using the larger brake shoes from two sets. But, I was not sure. Alan, is there a larger spring set to help the brakes release faster? Suggestions. Thanks to all and the IM's. How do you get the shoes to "set" better in the drum? You can see where they do not touch all the way around.

Robert

[Myron Piatek]

I seem to recall a looooong time ago that someone had a machine that could surface the drum shoe arc to fit the diameter of the drum. But I haven't seen or heard of anyone doing that in recent memory. Perhaps an old timer or old school shop may still have that capability. The practice could have been discontinued due to the dust it created, even after they quit using asbestos. (At least I think they use to.)

On a side note.....the converter is a factor in how high one can go before the brakes can't hold it. One can usually bring the rpm's higher with a looser converter.

[Alan Roehrich]

Robert, new springs might help them release faster, but that's just more pressure opposite the pedal pressure, so it won't help hold it.

Myron is correct, there is (or was) an arch grinder made to correct the arch on shoes, so they fit the drum correctly. Even when I worked in a shop in the very early eighties that had one, they were extremely rare, only a higher end shop that was pricey had one and had anyone that used them. It requires a person to measure the drum correctly, then set up the machine, and correctly set up the shoes. Adds a good bit to a brake job, so no one but the expensive shops used them. Back around 1982 or so, one shop in maybe 30 had one. It does make a real difference. Good luck finding a shop that does it now. Odds are, the owner is in his sixties, or older, and the shop is the highest shop in town, with a lot of long term customers.

[SSGN]

I was also told that switching the brake lines on the master from the factory setting is better (holds more pressure on the rear wheels) BUT I have never tried it and don't know anyone personally so this could be one of those old bench racing stories. Has anyone else tried this?
Thanks
Kevin

[Ron Gusack]

My 70 Nova held better on the starting line after we swapped the factory disc brakes for drums plus the drums were lighter. It's possible that there was a problem with the discs, but drums in the front worked better to stage. If I remember right, we picked up about 500 rpm over the discs.

[SSDiv6]

In addition to re-arching the shoes and putting larger wheel cylinders, try to find a brake relining shop and ask them if they would put the same lining material used on forklift brakes. The coefficiency of friction of the forklift brake lining is higher.

[Larry Hill]

Don't forget to check the rear drums for cracks every time you swap sides with the slicks, also its a good time to adjust the breaks. We could hold the cuda at 3200 rpm with 10 inch stock drums, of course changing the backing plates every year was required due to stretching the mounting holes.

[R. Thorne]

Used to arc brake shoes many years ago. Essentially it matches the arc of the shoe to the arc of the drum. If you can't find anyplace to do it ( check for HD truck shops), good used shoes would be an option (they have worn to fit the drums). Also, your brake drums may have been turned too much, check them against std diameter.

[Jim Cimarolli]

Originally Posted by Ron Gusack

My 70 Nova held better on the starting line after we swapped the factory disc brakes for drums plus the drums were lighter. It's possible that there was a problem with the discs, but drums in the front worked better to stage. If I remember right, we picked up about 500 rpm over the discs.

X2, the front drum brakes will fix your problem.