1955 Buick brake question

[Guest Tcarrasco84]

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[TD=class: alt1, bgcolor: #F2F2F2]Hello all, iam curious if anyone has ever put in a 60s style master cyl/booster firewall mounted in a 55 or 56 Buick. My Buick special is drum/drum and a original power brake car. The treadle vac was gone form the car and don't plan on going that route of putting one back in.I understand that the brake lines in the 55 special are 1 inch.so theoretically if I had a drum drum power booster that was 8 inches and the master cyl was set up for 1 inch I would think it would work I'm not looking to go complete resto on the car. Will something like this work? http://www.speedwaymotors.com/8-Inch...ster,9557.html

What have you used? Let's talk. Thanks everyone, and happy new year! Any advice is appreciated. Tony

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[PONTIAC1953]

you need to rethink not putting a treadle vac back in. now if you wanted to put in a buick standard master cylinder set up in the car and install a hydrovac between the standard master cyl. and the four wheel cyls, that would work. your best choice needs to be find another treadle vac set up that's correct for your 55 buick, and restore your car's brake system as designed by, and offered by buick in 1955. charles coker, 1953 pontiac tech advisor.

[keiser31]

Go here and ask...Hokey Ass Message Board - THE H.A.M.B.

These guys do this stuff a lot. It's a hotrodder's site, but they have talents, too.

[Guest Tcarrasco84]

Yea I've asked there with no such luck. And would rather just go with a firewall booster.thanks

[keiser31]

I thought I just read an answer to your post on the H.A.M.B. It is new years day, so it may take a while to get some answers.

[PONTIAC1953]

Yea I've asked there with no such luck. And would rather just go with a firewall booster.thanks

so you would rather degrade the value of your buick, by sticking with the idea of modifying your buick's brake system with something the car was not design to have, instead of finding the stock parts that are currently missing, and are not hard to find at all, and by staying with the correct parts, keeping your buick's market value at the level it deserves to be at ?, charles coker, 1953 pontiac tech advisor. p.s. there was, and is nothing wrong the original treadle vac system.

[Guest Tcarrasco84]

Wow a little hostile, I never plan on having this car stock, and it doesn't really interest me. And as far as the value being lowered I could care less it's my car and never going to sell it.

[Marty Roth]

Charles,

While I totally agree with you, it is still his option to degrade his Buick.

I just hope that his modification does not become a safety hazard on the highway, both for his sake, as well as the guy or gal, or kid he needs to avoid.

GM knew what they were doing when the car was designed....

Different or new does not always mean better.

I concur that the Treadle-Vac is the best way to go. Mine works great on the '54 Caddy.

But again -- not everybody is wiling to accept the wisdom which comes with experience

[PONTIAC1953]

Wow a little hostile, I never plan on having this car stock, and it doesn't really interest me. And as far as the value being lowered I could care less it's my car and never going to sell it.

a little hostile ?, lol, no, that wasn't my intention. i'm glad to hear that you never will sell it, because that is what i made up my mind about my 1953 pontiac chieftain custom catalina in 1973, when i was 17, and paid $150.00 for the car with my own money. i still have the car today. keep us informed with your progress. pictures please. charles coker, 1953 pontiac tech advisor.

[Marty Roth]

Tcarrasco84,

Sorry you did not get the information you wanted to hear,

but many members on this FORUM prefer originality,

after all - that is one of the primary concerns of Antique Automobile Club of America.

We certainly want to keep it all on a civil basis.

We have many technical genius members here, and your query could be addressed.

Personally, I think that there may be safety issues with your planned direction.

and as Keiser31 stated,

"I thought I just read an answer to your post on the H.A.M.B. It is new years day, so it may take a while to get some answers."<!-- google_ad_section_end -->

[PONTIAC1953]

Charles,

While I totally agree with you, it is still his option to degrade his Buick.

I just hope that his modification does not become a safety hazard on the highway, both for his sake, as well as the guy or gal, or kid he needs to avoid.

GM knew what they were doing when the car was designed....

Different or new does not always mean better.

I concur that the Treadle-Vac is the best way to go. Mine works great on the '54 Caddy.

But again -- not everybody is wiling to accept the wisdom which comes with experience

thanks marty, for your thoughts. i know i upgraded my 53's standard brake master cylinder in 1977 with 54 pontiac treadle vac set up, it was all a simple swapping of parts. i learned many years laters that after the 54 pontiacs started production, pontiac urged it's dealers to invite 53 pontiac owners to come back in if they wanted to get the treadle vac system. i hope the 55 buick special owner will take in stride, some well founded, and hard learned advise from those of us whose odometer has already gone around a time or two. charles coker, 1953 pontiac tech advisor.

[MrEarl]

A 55 Special with power brakes is a rare bird. Not sure why you would necessarily want power brakes but if you are going to use this car as a daily driver can certainly understand why you'd want a safety net of a dual master cylinder. The closest I know of is a early Corvette unit that comes from Master Power Brakes. It has a 3 bolt mount flange but I think you'll still need to fabricate a longer rod. They also have a remote fill for it so you won't have to remove the floor mat.

Master Power Brakes - CORVETTE DUAL MASTER CYLINDER CONVERSION KIT

Edited January 2, 2013 by MrEarl (see edit history)

[Guest Tcarrasco84]

I'm going with something like this mounted to the firewall. 8 inch booster will provide enough braking power to stop the old girl 8" Dual Brake Booster Master Cylinder Firewall Swing Pedal Kit Street Rat Rod | eBay

[joe_padavano]

I'm going with something like this mounted to the firewall. 8 inch booster will provide enough braking power to stop the old girl 8" Dual Brake Booster Master Cylinder Firewall Swing Pedal Kit Street Rat Rod | eBay

Is that 8" booster a single or dual diaphragm unit? A single diaphragm in that small a diameter is unlikely to provide enough boost. Keep in mind that the factory GM single diaphragm boosters were 11". Also, the master cylinder in that photo appears to be a disk/drum unit. You'll want a drum/drum M/C. Personally, I'd simply use a factory style booster from a wrecking yard with a drum/drum M/C from a mid-1960s GM full size. Obviously you'll need to do some plumbing changes to accommodate the dual circuit brakes. You can use a factory-style drum brake distribution block (NOT a proportioning valve) but that's only mandatory if you desire the differential pressure switch and associated BRAKE light on the dash. If not, simply plumb the rear M/C port to the rear brakes and use a brass tee to split the front M/C port to the two front brakes. This is both easy and a good safety measure for a regularly driven car. I'm struggling to understand the comments above about this becoming a "hazard" on the highway...

[Ben Bruce aka First Born]

No need to struggle, Joe. Some have some wild ideas. I like your suggestion.

Ben

[CarlLaFong]

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[TD=class: alt1, bgcolor: #F2F2F2].I understand that the brake lines in the 55 special are 1 inch. Any advice is appreciated. Tony

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It's been many years since I sold my 55 Special, But I do know that it did not have 1 inch brake lines, nor has any other car that I've ever owned or worked on. It would take 10 gallons of fluid to fill the system!?!?

[PONTIAC1953]

It's been many years since I sold my 55 Special, But I do know that it did not have 1 inch brake lines, nor has any other car that I've ever owned or worked on. It would take 10 gallons of fluid to fill the system!?!?

john, you are so right, lol, i think the brake lines are more like 1/8th or 3/16th in size, i know the master cylinder on my 53 pontiac is 1 inch, the front wheel cyls are 1 1/16th, and the rear wheel cyls are 7/8th size. charles coker, 1953 pontiac tech advisor.

[PONTIAC1953]

Is that 8" booster a single or dual diaphragm unit? A single diaphragm in that small a diameter is unlikely to provide enough boost. Keep in mind that the factory GM single diaphragm boosters were 11". Also, the master cylinder in that photo appears to be a disk/drum unit. You'll want a drum/drum M/C. Personally, I'd simply use a factory style booster from a wrecking yard with a drum/drum M/C from a mid-1960s GM full size. Obviously you'll need to do some plumbing changes to accommodate the dual circuit brakes. You can use a factory-style drum brake distribution block (NOT a proportioning valve) but that's only mandatory if you desire the differential pressure switch and associated BRAKE light on the dash. If not, simply plumb the rear M/C port to the rear brakes and use a brass tee to split the front M/C port to the two front brakes. This is both easy and a good safety measure for a regularly driven car. I'm struggling to understand the comments above about this becoming a "hazard" on the highway...

i guess joe has never driven a treadle vac equipped car, single diaphram and the diameter is about 7 or 8 inches. providing all the vacuum boost needed to stop the car. charles coker, 1953 pontiac tech advisor.

[bhambulldog]

Here

1955 super master cylinder and brake upgrade questions

Anybody switched to a dual reservoir master cylinder?

Master Cylinder/Booster options for '57 buicks.

[Guest Skyking]

It's been many years since I sold my 55 Special, But I do know that it did not have 1 inch brake lines, nor has any other car that I've ever owned or worked on. It would take 10 gallons of fluid to fill the system!?!?

I saw that earlier above and thought it was a misprint, that's why I didn't answer.:confused:

[bhambulldog]

When he said 1" I think he means the linings, the shoes, not the lines.

Here's another right here on this forum;

http://forums.aaca.org/f118/1955-disc-brake-conversion-kit-297355.html

[CarlLaFong]

1 inch shoes? My wife's moped has shoes wider than that

[bhambulldog]

:confused:

Yeah, well so does the Roadmaster.

I knew the Special had smaller brakes......:eek:

[CarlLaFong]

:confused:

Yeah, well so does the Roadmaster.

I knew the Special had smaller brakes......:eek:

Specials and Supers have 2 1/4" shoes. Roadmasters have 2 1/2".

[joe_padavano]

i guess joe has never driven a treadle vac equipped car, single diaphram and the diameter is about 7 or 8 inches. providing all the vacuum boost needed to stop the car. charles coker, 1953 pontiac tech advisor.

A treadle vac is NOT the conventional booster design in the photo. I HAVE driven cars like that. More to the point, the treadle vac applies force on the brake pedal arm and uses leverage. The conventional booster in the photo is in-line with the M/C and has no additional mechanical advantage. Your comment is neither correct nor helpful. Sorry.

[joe_padavano]

When he said 1" I think he means the linings, the shoes, not the lines.

Neither. It's the diameter of the master cylinder bore. 1" is very common for GM drum brake master cylinders.

[bhambulldog]

I understand your desire for a dual master cylinder.

We know now that,

Your brake lines are something smaller than 1"

And

Your brake linings are something larger than 1"

I have posted links to others that have gone the dual cylinder route.

Good luck to you,

Bulldog

[PONTIAC1953]

hi joe, you're mistaken about how the treadle vac system works, it does not apply pressure to the pedal arm, it acts like almost every other power brake set up, it allows the driver to apply less foot pressure on the brake pedal, and with vacuum boost, applies more pressure to the master cylinder to move brake fluid out to the wheel cylinders and apply the brakes shoes to the surface of the brake drums. a hydravac takes standard master cylinder hydraulic pressure, and with a vacuum booster, applies more pressure to the wheel cylinders with the hydravac master cylinder. i have never in 40 years, seen any kind of power brakes apply pressure to the brake pedal's arm. charles coker, 1953 pontiac tech advisor.

[PONTIAC1953]

here is what a treadle vac set looks like, the location of the pushrod behind the pedal is different than later powerbrakes set moving the pushrod up onto the pedal's arm, but everything works the same way as i explained in my earlier post to joe. charles coker, 1953 pontiac tech advisor.

[joe_padavano]

i have never in 40 years, seen any kind of power brakes apply pressure to the brake pedal's arm. charles coker, 1953 pontiac tech E]

Charles,

The booster on the 61-63 Skylark and F-85 is located under the dash and applies force to the pedal arm, not the M/C directly. In any case, you cannot compare a treadle vac to a modern diaphragm style booster. An 8" single diaphragm booster will provide only limited assist unless the engine produces a VERY high manifold vacuum. There's a reason why GM used an 11" booster on most of it's large cars.

[PONTIAC1953]

if someone wants to compare a treadle vac to any other type of power brake system, it is perfectly ok to compare. and most of GM's LARGE CARS had treadle vac power brakes from 1952 to 1958. charles coker, 1953 pontiac tech advisor.

[RiKi5156B]

Keep in mind that if you use any booster other than the treadle under the floor you will have to change the brake pedal to a manual brake model. The brake pedal for a treadle is nearly 1 to 1 ratio and I guarantee you will have a difficult time stopping regardless of the booster. The manual brake arm is about 6 to 1. After having my booster rebuilt twice by the "best" treadle vac rebuider in the country and having it leaking vacuum both times I went to manual. Works great, Rich