mechanical vs. hydraulic brake systems

[Slowplane]

Originally Posted by Tom Foster

Of course, becuz they're all interrelated, doncha see. Using better oil will lead to better engine life, which means you'll want to drive it more, which means you'll want better brakes, and when you get better brakes you'll want it to start and run better, and so on, and so on.
It's a slippery slope we're on here, my friends. Just keep on using that ground-up dinosaur oil that's been in it since you pulled it out of the barn ten years ago, since by G_d that's what Henry put in there!
(Please, ever'body, the last paragraph was a Stephen Colbert-style rant and was intended wholly as satire.)
Fearless

Tom I like yer way o'thinkin'!..

[bikejunk]

I dont have a garage queen or parade car , but I do have (I think) really well adjusted stock 1930 model A brakes and It drives in the most congested part of the country with the worst drivers of all nations - norther New Jersey/ New York and the Bronx. keeps up and stops no problemo

oil- 15-40, blackwalls, hand signals, stock brakes, generator, old fudy dudy, points 6 volt =fun as hell

[CarlG]

Originally Posted by Slowplane

....so if I run multi-grade detergent oil, I should dump my mechanicals, or switch to an alternator??

Only if you insist on running anti-freeze in Summertime Phoenix.

[Growley bear]

Any way, it all boils down to where the rubber meets the road.

[Terry, NJ]

My Coupe with Hyd. brakes is now off the road because of it's hydraulic brakes need a specialty fitting that seems to made out of "Unobtainium" The system is a little screwy, workable, but screwy. Last winter, I put a new MC x2, to replace the old MC x1 and it worked OK until lately. But I'd be much happier if I did not have a MC. There seems to be littgle doubt that the mechanicals can do do anything the hydraulics can do. There is no advantage! Higher Tech? who needs it? If I could take it back cheaply, I would! (I bought it that way)
Terry

[mhsprecher]

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Not that this will add much to the conversation, but my 30 TS with cast iron drums stops great. My 28 roadster with steel drums does not stop very well. I suspect the old drums are worn beyond spec. My plan is to replace the steel drums on the 28 with cast iron. When I replace those drums, I will have my old ones checked to confirm my suspicion. I adjust my own brakes using the Les Andrews/Service Bulletins method. Both mechanical braking system appear to have been properly restored before I bought my cars.

FWIW, I have rebuilt many master cylinders and wheel cylinders in my day, so hydraulic systems do require maintenance. I had an 1971 Toyota Landcruiser that had two wheel cylinders per wheel and required constant adjustment of both shoes per wheel, as I recall. It was a devilish system that drove me nuts. The LC was one of our daily drivers, not something I would recommend given the other shortcomings of the vehicle.

[Synchro909]

I've read every post here and can't say I've learnt anything new so now I want to throw in something to start it all over again.
What do you think of putting a vacuum operated booster on mechanical brakes? I've seen it done (on the cross shaft) and the owner swears by it. Best of both worlds???

[tbirdtbird]

Pics?

[Big hammer]

What's needed is a better anti-lock system for mechanicals! My leg doesn't work fast enough :-) More fun to slide skinny tires !!!

[Bob C]

Originally Posted by tbirdtbird

Pics?

Here's some pics.

[Purdy Swoft]

Originally Posted by Synchro909

I've read every post here and can't say I've learnt anything new so now I want to throw in something to start it all over again.
What do you think of putting a vacuum operated booster on mechanical brakes? I've seen it done (on the cross shaft) and the owner swears by it. Best of both worlds???

It probably would work for a while But consider the complication and parts that would be required. It would be another place for a vacume leak to happen. Why complicate a simple system that works great if properly set up and in good working condition.

[Y-Blockhead]

Originally Posted by Synchro909

What do you think of putting a vacuum operated booster on mechanical brakes? I've seen it done (on the cross shaft) and the owner swears by it. Best of both worlds???

So your suggesting modern day POWER brakes on a Model A. How about throwing in disc brakes also??

Originally Posted by Purdy Swoft

It would be another place for a vacume leak to happen.

Then we could install an electric vacuum pump so we don't have leaks...

[William Kelchner]

I too like keeping things original. My car had hydraulics on it when I bought it and I have always wanted to go back to mechanical brakes until I discovered I would have to sell my first born and most every thing I own to afford all the parts to convert back.

[MrBruce]

Originally Posted by ericr

surely the subject of brakes creates a lot of attention herein, and one often sees a statement that properly-adjusted mechanicals are as good as hydraulics.

without appearing as a wise-ass, I'd like to know the basis for that statement. Are there owners who have switched to hydraulics and wish to affirm the claim? Has anyone switched back?

If going hydraulics means changing other components, I'm not sure that makes it a level playing field. and as is often observed, many of our restorations are not up to original specs. But nor is there anyone left alive who drove the cars when new that can render a comparison opinion about our restorations.

I've driven our 31 S/W Town Sedan for 30 years with the mechanical brakes and like any good automobile you need to maintain it. I put it up on jack stands at our annual tune and test adjust them as Ford suggests in the service manual and I don't really think about it when I hit the brake pedal as it stops straight and when I want it to. I don't tailgate just in case I have to stop quick, but I can lock up all four wheels which doesn't stop me as well as not braking them loose. I will stick to the 30 years of 'fact" that when done to spec they work like Ford intended them to work.

[SSsssteamer]

I have about 15 collector cars and I cannot drive them all enough to keep them turn key fresh. The cars with the mechanical brakes have always stopped well and reliable after years of storage. The hydraulic brakes usually caused me grief from years of sitting. Usually the wheel cylinders became frozen up from sitting too long. I have found the only time hydraulics has helped is when I changed my Stanley's two wheel mechanical brakes to disc brakes. The new disc brakes do not fade like my drum brakes did all of the time. The disc brake conversion that I did is when I installed disc brakes into our 1916 Stanley 12 passenger Mt. Wagon that weighs 5,500 pounds empty. (then add 2,000 pounds of passengers) Hydraulic drum brakes wouldn't have helped at all as I would have still had the same brake fade. The disc brakes made all of the difference, and they were completely hidden inside the 16" diameter brake drums. Since the Model A Ford has four wheel braking and is about one third the weight of my Mt. Wagon, I don't see any advantages in changing the model A mechanical brakes to hydraulic drum brakes. I did change to silicone brake fluid to give me more long term storage reliability.

[Synchro909]

[QUOTE=Y-Blockhead;1008581]So your suggesting modern day POWER brakes on a Model A. How about throwing in disc brakes also??


I've seen that done too. The discs were hidden inside dummy drums.
Y-Blockhead, You are clearly on the side of originality. Fine. Others are not and the amount they are prepared to deviate from original varies from person to person. I figure they are their cars so they can do what they want with them but I don't condone changes that are irreversible. That said, some of the work done by hot rodders is very nice.

[2935ford]

I have had both..........
Everything being equal on a stock Model A.......IMHO original properly installed and adjusted/maintained......... mechanical is the ticket.

Finding the very best original parts you can makes a big difference. Much of the newer re pop (offshore) parts simply will not do.

[Bob Bidonde]

EricR,

Brake system evolution from mechanical levers to hydraulic pistons was driven by the need to apply more force to stop heavier and faster vehicles, and to fit into automotive chassis having complex geometries. For example, in 1932 Ford increased the brake drum diameter because of the more powerful "Improved 4-Cylinder Engine," and the new V8 engine. To cope with the complex (curvy) chassis geometry of the mid to late 1930s, Ford first evolved to the use of brake cables instead of straight rods. However, by the end of the 1930s Ford finally yielded to the advantages of hydraulic brakes.

Consider these specific reasons for hydraulic brakes:
1. The increase braking forces applied to slow and stop heavier and faster vehicles would require brake levers too large for a practical fit into cars and small capacity trucks;
2. A small change in the diameter of the hydraulic brake master and wheel cylinders produces a significant increase in braking force using a very small increase in space;
3. Hydraulics have much less parasitic loss due to friction and wear than mechanical lever systems, so hydraulics are much more efficient;
4. Hydraulic brake systems are more easily fit to vehicle chassis' with complex geometry than mechanical lever systems;
5. Hydraulic brake systems have fewer parts making them less expensive to manufacture, install and adjust on the assembly line.

[Synchro909]

Looking for opinions on a set of 1948 Lincoln brakes I have but not yet installed. Everything is new from master cylinder to backing plates and drums. I have all of the hoses and fittings etc but just haven't got around to fitting them, now I'm starting to wonder whether I should. I think an important factor is I will be running 16" wheels which will require more brakes to lock up than the originals. I was thinking that the larger drums would help even if all else was equal.
Opinions based on experience please.

[ericr]

Originally Posted by Bob Bidonde

EricR,

Brakes system evolution from mechanical levers to hydraulic pistons was driven by the need to apply more force to stop heavier and faster vehicles, and to fit into automotive chassis having complex geometries. For example, in 1932 Ford increased the brake drum diameter because of the more powerful "Improved 4-Cylinder Engine," and the new V8 engine. To cope with the complex (curvy) chassis geometry of the mid to late 1930s, Ford first evolved to the use of brake cables instead of straight rods. However, by the end of the 1930s Ford finally yielded to the advantages of hydraulic brakes.

Consider these specific reasons for hydraulic brakes:
1. The increase braking forces applied to slow and stop heavier and faster vehicles would require brake levers too large for a practical fit into cars and small capacity trucks;
2. A small change in the diameter of the hydraulic brake master and wheel cylinders produces a significant increase in braking force using a very small increase in space;
3. Hydraulics have much less parasitic loss due to friction and wear than mechanical lever systems, so hydraulics are much more efficient;
4. Hydraulic brake systems are more easily fit to vehicle chassis' with complex geometry than mechanical lever systems;
5. Hydraulic brake systems have fewer parts making them less expensive to manufacture, install and adjust on the assembly line.

a most interesting explanation, thanks for the post. from what you are saying, hydraulics could require less foot pressure....