Booster for Bendix brakes : options, opinions?
 

I have a 35 woodie with 40 spindles and Lockheed brakes. My plan is to move to 53-56 bendix FRONT brake using F100 backing plates and drums. Assembling those parts now. While I am doing that, I am also planning to add a booster to my system. Car is currently outfitted with a dual master. It appears that I have two options for a booster.. a 55-57 Tbird midland or a VH44 big bore ¾” .. while chinese VH44 are available on eBay the bore is 5/16” and look to service 10” drums. Research suggests the VH44 as a better choice than the Tbird, since Tbird could be too “aggressive” . It also looks like I will need a space to run my 35 wire wheels and possible a change of wheel bearing (More info needed )

I am writing for any comment from folks who have done something similar.

Flatheadfan has posts of his Tbird set up, but he is not with us now.

Re: Booster for Bendix brakes : options, opinions?
 

I have a Midland unit with disks on front and drums on the rear. My master cylinder bore is 1". It works wonderfully for my '40. I have a pressure regulator for the rear drums to prevent premature rear brake lockup.

I also bought a VH44 which has about the same diaphragm diameter as the Midland unit. Jury is out on how well it works until the weather gets better here.

"PBR VH40 Booster
PBR VH40 Remote Brake Booster Designed to considerably reduce brake pedal effort without losing control of the brake application. Suitable for Disc Front/Drum Rear brakes. It is a Vacuum-Hydraulic Unit for power braking which utilizes intake manifold vacuum and atmospheric pressure for its operation. This booster is larger in diameter and generally more powerful than the VH44 and is available in many models to suit both disc and drum applications.

PBR VH44 Booster
Ideal for applications where a factory engine bay-mounted booster cannot be used due to space restraints. It is a Vacuum-Hydraulic Unit for power braking which utilizes intake manifold vacuum and atmospheric pressure for its operation. The VH44 is suitable for Drum brakes all round and is available in many models to suit both disc and drum applications."

This is a post I made not long ago about these boosters. Read the attachments too.

https://www.fordbarn.com/forum/showp...82&postcount=6

Re: Booster for Bendix brakes : options, opinions?
 

Glenn .. thanks for the reply..

I did read through a LOT of posts ,, and found you PDF file.. so thanks for that too!

I got a price from White Post (who bought out Ed) for the Midland for $595.
OR i can get a new PBR vh44 out of Australia for about $400 including shipping.
The VH44 has a 3/4" bore.
The generally available VH44 (chinese) from Ebay have a 5/16" bore.. Cheap at 64$. but could prove to be "undersized"

I will be installing a JEGS vacuum canister to be sure that I have plenty of Vacuum.. my 59AB has an ISKY 77 B cam that may draw down vacuum.

So I am currently researching to see if one is "better" than the other.
One thing for sure tho is that I will be using wilwood proportioning valve to assure the I can balance the system.

As noted I have a dual Master .. don't remember the manufacturer, but it is a very common unit. My 40 brakes are all stock lockheed. I operate the system with stock 35 pedals and the mechanical brake crossbeam arm. Master is mounted midships

BTW I am in Old Orchard Beach.

Re: Booster for Bendix brakes : options, opinions?
 

My 1957 Thunderbird had front disc brakes. The stock booster allowed me to feed the rear brakes from the master cylinder before the booster and the front brakes from the master cylinder after the booster.

Re: Booster for Bendix brakes : options, opinions?
 

"All power brake systems use engine vacuum to assist the normal operation of the brakes. Utilizing a vacuum cylinder or chamber with a diaphragm inside, they increase the brake line pressure and decrease the driver’s effort needed at the brake pedal to stop the car. Engine vacuum from the intake manifold acts on one side of the diaphragm, and valving devices let air (at atmospheric pressure of 15 pounds psi) in on the other side. As you depress the brake pedal, air is let into the cylinder, and the difference in pressure between the vacuum side and the atmospheric side causes the diaphragm to move. The diaphragm moves a rod connected to the master cylinder’s piston and increases the brake fluid pressure to the wheel cylinders. After the brake pedal is released and the supply of atmospheric pressure is cut off, springs in the cylinder return the diaphragm to its normal position and stop the assist action.

With the integral-type units, the diaphragm works directly on the piston of the master cylinder, but with the multiplier types we are concerned with here, the power brake unit has its own hydraulic cylinder. Mounted away from the master cylinder, the multiplier is connected to the master cylinder by a hydraulic line. The diaphragm works the piston of its “slave” cylinder, which in turn is connected by a line to the wheel cylinder junction fitting on the frame, and the slave cylinder adds the necessary extra braking pressure to the wheels. When the brake pedal is held at a steady position, pressures on the diaphragm are equalized by a control valve, slowing down the assist action so you don’t lock up the wheels every time you step on the binders.

Re: Booster for Bendix brakes : options, opinions?
 

Good, no reason to boost the rear.
I thought all the stock '57 Birds used the Midland unit which only has one inlet and one outlet?

Re: Booster for Bendix brakes : options, opinions?
 

Oh, I never have a problem with the booster being too aggressive. It operates just like any other power brake system in my experience.

The VH44 has DIN type of brake line threading. These require a "bubble type" brake line end versus the SAE double flare. I found that I could not get a leak tight joint for one of the DIN fittings. I re-threaded a 1/8 NPT by 3/6 male inverted flare fitting so the 1/8 NPT was changed to a 3/16-24. I used blue Loctite threaded into the VH444 and problem was solved.

Re: Booster for Bendix brakes : options, opinions?
 

Glenn I have vacuum plate that will sit under my 97 carb

I was also thinking about using the vacuum canister to feed my vacuum Trico wiper...

Also, do you have any info on the chinese units... effectiveness, capabilities, et.c

Re: Booster for Bendix brakes : options, opinions?
 

As posted by 'glennpm':
https://www.fordbarn.com/forum/attac...1&d=1772910195

Re: Booster for Bendix brakes : options, opinions?
 

Okay, I understand the canister usage now.

I can't comment on function for the VH44 however, my Midland is basically the same design and it works very well.

Re: Booster for Bendix brakes : options, opinions?
 

Regarding this discussion,

"I got a price from White Post (who bought out Ed) for the Midland for $595.
OR i can get a new PBR vh44 out of Australia for about $400 including shipping.
The VH44 has a 3/4" bore.
The generally available VH44 (chinese) from Ebay have a 5/16" bore.. Cheap at 64$. but could prove to be "undersized"

I believe this is a mistake by the Chinese in description. I bet the 5/16" is referring to the "VALVE PISTON ASSEMBLY" and NOT the slave cylinder bore.
-5/16" OD slave would NOT move enough fluid volume
- The Chinese copied the AUS design! and they sure wouldn't come up with a change leading to a non-functioning booster."

I found a table this morning confirming my comment. The slave cylinder is most likely 3/4" diameter but may be 5/8"

https://www.fordbarn.com/forum/attac...5&d=1772978493

Re: Booster for Bendix brakes : options, opinions?
 

Just a mention on the early 59's F100 brakes - you can install the 60's F100 self adjusting hardware with a few mods ti the grease shield. I have them on my avatar and they work pretty well.

Re: Booster for Bendix brakes : options, opinions?
 

Really? I'm really curious about this. Never knew.

Re: Booster for Bendix brakes : options, opinions?
 

Here you go Tim

Re: Booster for Bendix brakes : options, opinions?
 

Glenn. Most of what I read suggest that I may need grind my 1940 spindles to fit the 56 assembly. do you know if this is a simple grind or will I be at it all day? other reads suggest that I use 46-48 spindles (Curt Baker), but I really don't want to tear up that much if the grind is mostly pretty straight forward,

Re: Booster for Bendix brakes : options, opinions?
 

Just bought a pretty clean complete 1956 F100 set up without hubs for $175.

Re: Booster for Bendix brakes : options, opinions?
 

Pictures of F-1/F-100 brakes with later self-adjusting hardware.

Parts needed:

self-adjuster kit H2540
self-adjuster kit H2541
self-adjuster kit hardware H7144

Also need to notch the shoe retainer (or use a later retainer) to clear the forward spring.

Re: Booster for Bendix brakes : options, opinions?
 

Simple amount of grinding to clear the wheel cylinder.

The spindle in pictures is ground on both sides for unknown reasons (symmetry?). Only one side actually needs to ground.

The 144116 inner bearing used to fit F series hubs has a square inner corner; I usually use a die grinder to bevel that edge to match the radius on Ford spindles.

Re: Booster for Bendix brakes : options, opinions?
 

Rich... you caught me off guard with this data! in all my research and old school instructions, I have not come across this self adjusting hardware kit. Is that something that further improves the braking ability of the 1956 F100 brake set up. I note that the gear seems to apply to the late 60's. What can you tell me?

Re: Booster for Bendix brakes : options, opinions?
 

Thanks for those detailed pictures. I can see what needs to be done.. just allow clearance to accommodate the cylinder housing.