New owner with a million questions. Hydraulic brake Followup

[VFRhugh]

In my first post I mentioned I'd converted to hydraulic brakes. No need to debate but it was the cumulative wisdom is this forum and Les Andrews Vol.II that sealed the deal. As you might guess it wasn't exactly like the book said but I'm very happy with the way it turned out. After about 50 miles of break in the car stops great. On thing I didn't mention is I used a vacuum boosted master cylinder. Peddle pressure is similar to a modern vehicle. I feel a lot safer on my daily trips around town. In today's world other drivers seem to have one eye on the road an the other on their smart phone. Whoa is more important than go these days!
Hugh

[Mike V. Florida]

As long as you feel it was money well spent, that is all that matters.

My mechanical brakes can, stop the car and even lock up all 4 tires as well, but again, it is what you feel about the car that matters and if juice brake is what it takes to get you on the road often, then I give you two thumbs up!

[Synchro909]

What Mike says X2

[Jacksonlll]

How did you do the emergency brake?

[VFRhugh]

I used the stock emergency brake handle, linkag & cross shaft. Cables with turn buckles from the cross shaft arms back. Easiest part of the job.
Hugh

[jhowes]

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As I get older the idea of vacuum assist brakes are interesting. . Can you give me any details on how you did this, did you need a vacuum pump?, where is it mounted?, Is this a kit or did you use an existing unit from some modern car? Thanks in advance, Jack

[Terry, NJ]

Not to criticize your choice, but I own 3 Mod A s, a Town Sedan (Being restored) and two coupes, all 1930. Two of them have hydraulic brakes and the newest coupe is mechanical.
The mechanicals stop every bit as well as the hydros. I thought that they would be more sluggish in their reaction but they may be a little quicker. And I don't have to crawl underneath and bleed them. I've replaced the master cyl. in my coupe and I'm having a lot of trouble getting all the air out of the system. Especially in the rear. I put a dual M.C. and changed it from a single system. This means it has two circuits,front and rear, instead of the old single circuit. All in all, I wish they were all mechanical. I believe that there's no real advantage to hydraulic brakes.
Terry

[VFRhugh]

Jack,
My intake manifold just had a boss for the wiper connection so I drilled and tapped it using 1/8"npt 3/8" hose barb fitting for the vacuum source. The booster is a 7" single diaphragm booster. They are available for about $100 online. Speedway motors is a pretty good place to look. I used a single reservoir system with a 1" bore piston. If you already have hydraulic brakes adding the booster shouldn't be that big of a job. The booster is 3 5/8" deep and 7" o.d. so you'd have to have that much space available.

I bought all my parts including the master assembly from Dick Sparks. He is on the forum and designed the bell crank/mounting plate assembly. The mounting position is shown on page 2-27 figure 27 (A) in Les Andrews Mechanics Handbook Vol II. Everything is pretty tight but works great so far. Dick recommended DOT 5 brake fluid because it isn't hygroscopic and should work well long term. I cut a hole under the front seat and use a stock battery cover for MC service. I also use quick release pins on the front seat. With speed bleeders I had no trouble bleeding the system.

I know this isn't for ever body but it works for me. I haven't made any irreversible changes and saved all the old parts if the next owner wants put it back stock.
Hugh

[mshmodela]

Happy that the new breaks turned out well for you.

[1931 flamingo]

This is a conversion that's been going on since probably 1939. Many people understand the hydraulic sys better than the mechanical. JMO
Paul in CT

[anteek]

Mike V touches on an issue. Mechanical brakes lock up but don't reduce vehicle speed like juice brakes and this was proven many times years ago. We would still have them if they were really better.

[jhowes]

Hugh, thanks for the reply. I am attempting to vacuum boost the mechanical system. I will post my results when I have some. Jack

[Bob Johnson]

I for one would like to see the proof that hydraulic brakes are better / stop better than mechanical brakes. I do not recall any proof that I have seen.

Bob

[bikejunk]

I am going to say that as far as stopping the vehicle they are the same but hydraulic brakes self adjust better than a mechanical system and aren't effected by Ice and snow under the car (read that in a 1930's motor magazine) - I love my rod brakes -

[Arlyn Bieber]

It has been my experience Hydraulic brakes are better than worn out mechanical brakes. However properly restored mechanical brakes with new cast iron drums and properly adjusted are equal to hydraulic brakes and cheaper also. Another plus is you don't have to drill holes in the frame, find a place for the master cylinder, chop up a crossmenber etc. I have seen more shoddy hydraulic brake jobs than you can shake a stick at. Also changed some back to mechanical brakes.

[updraught]

When I went looking for a new mountain bike, I could choose between hydraulic or cable disc brakes. I was told that the hydraulic have better "feed back" than the cable version, but maintenance is more difficult.

Most braking involves lots of "feed back". I assume the feed back is different between mechanical and hydraulic brakes on a car as well.

I'd like to know if one or the other work better with radial tires which should help with the "lockup".

[Tom Wesenberg]

The other day I had to hit the brakes hard on my modern car due to some jerk driver. The rear brake line blew and the pedal went to the floor. I had to turn sharp right to jump the curb and drive on the grass to avoid an accident. Dual master cylinders are a joke and give very little braking when one side goes. This is the 4th brake failure in the past 15 years due to salt rusting the brake lines. I might have to convert my modern car to mechanicals.

Stick with the original mechanicals because they are safer.

[Mike V. Florida]

Originally Posted by Terry, NJ

Not to criticize your choice, but I own 3 Mod A s, a Town Sedan (Being restored) and two coupes, all 1930. Two of them have hydraulic brakes and the newest coupe is mechanical.
The mechanicals stop every bit as well as the hydros. I thought that they would be more sluggish in their reaction but they may be a little quicker. And I don't have to crawl underneath and bleed them. I've replaced the master cyl. in my coupe and I'm having a lot of trouble getting all the air out of the system. Especially in the rear. I put a dual M.C. and changed it from a single system. This means it has two circuits,front and rear, instead of the old single circuit. All in all, I wish they were all mechanical. I believe that there's no real advantage to hydraulic brakes.
Terry

He had already done the conversion so there was no need to try to convince him otherwise. If he was asking about converting then you would have heard different from me and I'm sure others. He is happy with it, he will now drive it.

[bbrocksr]

Originally Posted by Tom Wesenberg

The other day I had to hit the brakes hard on my modern car due to some jerk driver. The rear brake line blew and the pedal went to the floor. I had to turn sharp right to jump the curb and drive on the grass to avoid an accident. Dual master cylinders are a joke and give very little braking when one side goes. This is the 4th brake failure in the past 15 years due to salt rusting the brake lines. I might have to convert my modern car to mechanicals.

Stick with the original mechanicals because they are safer.

Tom, I wonder why all modern cars went to hydraulic brakes? Does that mean modern cars aren't safe? Are all the manufacturers wrong or could you be wrong? Bill

[hardtimes]

Originally Posted by Tom Wesenberg

The other day I had to hit the brakes hard on my modern car due to some jerk driver. The rear brake line blew and the pedal went to the floor. I had to turn sharp right to jump the curb and drive on the grass to avoid an accident. Dual master cylinders are a joke and give very little braking when one side goes. This is the 4th brake failure in the past 15 years due to salt rusting the brake lines. I might have to convert my modern car to mechanicals.

Stick with the original mechanicals because they are safer.

'4th in 15 yrs'... ! Someone may be trying to tell YOU something,eh
Hm, I haven't had a 'brake failure'....ever....even with mechanical brakes !!

Well, there WAS this one time when a '28 chev went thru an intersection...without my permission...and almost wiped out an officer in a blk/wht ...mechanicals sheesh !!!!

I'll admit that I'm expecting BIG improvement with the Lincoln brakes now, oh and with addition of Hugh's booster suggestion !