I'm trying to go traditional on a '30 Model A Coupe, fenderless, 4 in drop I beam axle, hairpins. I like the traditional look of drums, but the technology of discs. Rears will be drums. Can't decide. Your opinion ?
If you're old enough to know how to drive a car with drum brakes (don't tailgate! turn the damn cell phone off!) then go with drums.
If you do the drums, go with self energizing like F100 or early Lincoln (Wilson Welding). Cuts way down on the seat puckering.
What Primed 34 said. The new drum brakes available now make discs obsolete on a light car. If you have a five speed in the car, it only needs to stop from 20 MPH anyway. If you pull a trailer in the mountains, more brake power is always a good thing.
it all depends on the rest of the car. SBC with a tunnel ram? discs. flathead? drums if a person is not going all out traditional style then theres no sense in putting drums on it.
drums can be setup reasonably well... self energizing, good linings arced to the drum, maintained religiously and driven with respect... guess it depends on your driving style, the style of the car and the tires. have some skinny bias plys on the front, discs aren't gonna be that much better than drums...
I would think traditional would be drums. For what it's worth, we are running drums on our '29 Coupe and I have found them to be plenty of brake for that little car. I think if it was a heavier car, discs would be important, but our Model A weighs next to nothing.
I've seen front disks that were disguised inside a false drum that would be the best of both worlds. In the real world I would use disks if stopping were a priority and drums to be totally tradional. Remember that almost all of the stopping is done by the front brakes and if you run a skinny tire it will lock up and slide under heavy braking. Drivers "ed" in the days of drum brakes said to leave at least one car length for every ten miles an hour of speed in order to stop. They didn't just pull that number out of thier ***.
I don't know what all you people are saying, I've driven the **** outta of my hot rods and never ever had an issue with properly working drum brakes. Even driving it really aggressively, through huge *** mud puddles, standing on it, never had a problem with my drums. These aren't big fat Chevelles, these are nimble little hot rods!!
I will go against the grain here....use discs. Driving is about fun.Being able to stop in most situations will keep you driving. I grew up with drums and now I won't have them on any car if I can help it.Discs are simpler,cheaper,easier to replace and safer.I think that discs look better too, they have that mechanical look....kinda like a flathead all decked out.And thats my 2¢.
They're referring to the brake design, and in particular, the Bendix Duo-Servo brake used on early Lincolns and F-1/F-100 trucks. All drum brakes are self energizing, but the later Duo-Servo design is much more efficient than the first non-servo Lock-Heed brakes Ford used from '39-'48.
so if you're running skinny tires, disk brakes are not necessary? That works ok for lower speeds, but leaving a couple seconds between you and the car ahead (time instead of distance) is probably a better rule of thumb.
Do a search for "drum brakes" in the tech archives... You'll get ten good threads with info on drum brakes and a list of links to several others...
Bob...There are self energizing (aka Bendix) brake ***emblies available for early Fords...and they work with the original 11" drums, on the original axels / spindles. Well worth the $$ !! Just bolt them on, , they come fully ***embled on backing plates, as well as being available with parking brake mechanisms for the rear ones. Saves a lot of time, and "pucker factor" 4TTRUK
The problem with "self-energizing" drums - one leading shoe pushing on the other - is that their action isn't directly proportional to effort: that is to say their action isn't linear, and as a result they aren't as easy to modulate as discs or even regular drums. If one were cynical one could say this was a way the manufacturers saved on the cost of power brakes. Regular drum brakes also "self-energize" to the extent that the shoe pivot is offset from the inner face of the drum. A big offset makes for a greater self-servo effect, but a small offset makes for better feel. Most conventional drum set-ups have leading and trailing shoes on the rear brakes and twin leading shoes on the front brakes. The trailing shoes on the rear brakes give you some braking in reverse; otherwise you'd have barely any. Front brakes usually have the shoes pivoted on opposite sides (usually top and bottom) so both shoes are leading shoes. Racing brakes often had more than two leading shoes. The ultimate drum-brake set-up would comprise the biggest diameter drums you can find, amply ventilated through the backing plates, and three or four leading shoes - on the front brakes at least - without a lot of self-servo geometry. By the way, were drums ever vented by holes drilled through the friction surface? It seems at odds with contemporary area-based thinking, but subsequent experience suggests that there might be something in it.
My car in my avatar weighed 3685 before discs on the front and stopped fine from 140mph just took a little bit. Only reason I switched was cost effectiveness going from ball bearings and hard to find parts. Make sure they are self adjusting and your lil car will stop fine.
I think the point about weight and tires is an important one. The modern cars we drive (my Dodge Ram truck) probably weighs 2.5 times what an early HotRod does, BUT it also has radial tires that have a contact patch that is 9 - 10" wide. That truck can stop extremely well -- even for a big vehicle. Now if I put a much narrower tire on it . . . would change it dramatically. When we put the "big n' little" tire package that many of us like on our hotrods, and we're running bias-ply tires, we do degrade the ability of ANY brake to do what it is capable of. Would my car stop a LOT better with bigger radial tires on the front . . . no question, AM I going to put them on -- nope. Guess I'll lay back in traffic just a bit . . . and the car won't be out in the middle of the working week rush hour anyway. As a side note: I talked to Wilson Welding about this very question and he just laughed a bit and said -- "you're putting on big Buick full-size car drums and my brake setup (which are quite a bit bigger than what Ford used) . . . on a stripped down hotrod that weighs about 1/2 of a 58 Buick -- YES, it will stop very well!"
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