Disk drum vs disk disk Alot of car started with a disk drum conversion and later went to 4 wheel disk. My question is does it stop that much better and would you do it again?
I don't think I've ever swapped working drum brakes, for disc brakes. But then I usually build my modified cars out of parts cars.
Disc have been used on aircraft for years...Less operating parts...Less brake fade and a lot better in wet areas...If you really want traditional lets go back to T models with rear wheel brakes only,,, That would really work well in todays traffic...
Brakes are one area (steering is another) where being 'traditional' (drum, mechanical, etc.) might be a good thing to rethink. As we build or toys, we have to keep in mind the traffic we'll be driving in (if you're building a 'show queen', this doesn't apply)... Today's drivers don't give a shit that you have spent 6 years and multi-thousand $$$ building your rig, or that it is traditional. What they care about is you not interrupting their texting and talking, and being able to stop on a dime when they pull some dumbshit move! To protect your ride, investment and loved ones, install the most modern, reliable brakes you can (mechanical DO NOT fit this description!!). JMHO, but I'm right!
They don't really have rear brakes, either. There's the parking brake which are at each rear wheel, but when you are driving, you use the transmission brake band. Since the car can't go very fast, it's only scary, not terrifying, most of the time.
4 wheel heat shedding discs, dual piston calipers, dual master, adjustable prop valve and a 1" longer brake pedal for leverage. When I stomp the brake pedal, I want the fucker to stop right now. I don't want to hope it's gonna, maybe, stop. I don't want pedal fade. I don't want to use the emergency lane or a ditch for avoidance. I feel that my car stopping when I want it to is the traditional way brakes should work.
It depends on weight distribution. The more rearward weight bias, the more likely I'd want rear discs — not for sheer stopping power, but for fade resistance. I don't want my brake bias steadily shifting forwards the further I drive. Clean-sheet, there are ways to keep drums cool: large diameter, multiple leading shoes, smaller friction area at greater pressure to allow air circulation around the shoes, lots and lots of holes. Triple-leading-shoe Alfa Romeo drums from the '50s were seriously sexy, but you could go further: four, five leading shoes, centrifugal ventilation, scoops and fans and stuff. That'd be substantially harder to do than off-the-shelf discs, but may be lighter and would certainly be better fun.
To the Administrator, how is it possible to discuss rear wheel disc braking when you only a couple of days ago you guys shut down a Jag IRS help request, assuming that it was not Traditional enough, yet here we are!!!
I run disc/drums on my Ford. I had helped a guy with the drum fronts on his '62 T-Bird and that stopped well in the end. On a GM early '60's BOP car, the stock front drums were hard to beat for stopping power. If I had another down the road, I'd keep it front drums.
Actually, I considered a late Model T closed car, and I still may get one, one day. It could be a viable car here. I would have to choose my route and choose the time. I could easily take it town, drive in town traffic...go to the store...stuff like that. In the end I chose a '51 Coupe. As old as a '51 Coupe is, it can be a viable everyday car for me here. Notice I said for me here, not you, there.
Have you driven one much? I had one for a little while a year and a half ago...going to town was an adventure. There's one stretch where the speed limit is either 50 or 55, depending which way I go, and the car is pretty happy at 30. Stopping....you have to pay attention to what you're doing at all times, if you want to be able to stop in time. otoh, there's a fellow in Tucson who drives his all over the place.
Drum is fine, as long as they are self-energizing Bendix style. I've had my fill of stock 40 Ford (lockheed) brakes, I have a set of Lincolns on my 39 (bendix) and come over and take a ride and I'll throw you through the windshield at your request. I don't live in the mountains so I have never experienced drum brake fade. And yeah, riding in a Model T is an adventure! My dad had a 1915 touring and 45 mph felt like 100.
The only time I've been terrified by brake fade was in the mountains, in a car with the old BW overdrive, and I didn't have it locked out, at the wrong time. As long as you keep the transmission in a low gear, you're fine with drums on mountains. But it's kind of like the T, you have to pay attention all the time.
Jim, No, I have never driven one. I've seen them. I have researched them for years. Where I'm at, sometimes a car will not pass the house for 45 minutes. I can take the rural roads to town and come in the back way. Traffic in town is benign on main street in the middle of the day. It's a small town. There's the main drag which is a state hwy. Then there's the old main street to the side. If I stick to the side streets....it would be an adventure. You have driven one, you owned one...you know. When all was said and done, I chose the 1951 Coupe. It's not as limited. Also, I live in the Appalachian foothills, so this limited the T even more, to staying in the valleys.
I did drive mine to Tombstone, and Bisbee, they're each 20-30 miles away, and have to go down to the river, then back up to get to either. Speed limits are 45-65. There is some traffic, but it's not bad. I decided the car just wasn't going to work for that type of driving on any type of regular basis. Hills are a challenge, as you figured out. 20 HP doesn't go very far!
My T~Bucket has four wheel drums, and it stops amazingly well. On par with any modern car. Of course it’s a light weight car, with relatively large drums.
Things about a model T in the day average engine life 10K- 20 K drive them fast ( for them) for extended periods and the bearings won't like it. Take a trip say 50 miles you better have tools.
And then there was this guy who became addicted to brake fluid...he swore that he could stop anytime....
I was really hoping to find some one who went from disk drum to 4 wheel disk and thought it was worth it.
I did, on several vehicles. Traffic where I live moves fast and can be erratic. If I still ran drum/drum I'd be dead. If I still ran disc/drum I'd likely be injured, and sued out of existence. Tradition is only good for so much. Spent a whole lot of time in automotive engineering, and I have seen tens of thousands of pages that indicate very clearly that discs are vastly superior to drums in every way. They're also more expensive to produce than drums. Given the small margins on automobile sales if were drums were as efficient in any way as discs, they would be on vehicles, on all four corners. They are even disappearing from trailer trucks. If you want to run drums, run drums. Just be prepared for them to not function as well as the brakes on all of the other vehicles around you. And for heaven's sake please don't claim that drums are just as good as discs, they are not.
While drums may not be as good technically, you drive accordingly. No different than driving a big truck, or a model T, they dont stop. Pay attention, give yourself some space around you.
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