power brake booster question

[mr. fix it]

Hi there Brake experts!

Last fall I bought a Power brake conversion for my 66 Polara from Murry Park.
The kit included a power booster that I could use as a core charge.

I received a replacement BB but it is a slightly different shape than the one Murry included.

I looked up the application code for the rebuilt unit and it states it is for the Polara.

It measures up physically to the same as the core I have.

I am thinking the amount of boost I will get from the rebuilt unit since it appears to have a larger chamber.

I think I will get a little bit more duration of vacuum than the original style

The Summit Racing shows it fits as well but even Summit shows the original style with the number of the booster I received

http://www.summitracing.com/int/parts/aaz-54-73520/applications/make/dodge/year/1966/model/polara

Again, the application chart show it fits the Polara.

Have a look at the pics and let me know your opinion.

BTW: the original booster came off a "1966 Newport"

 

[68plymouth383]

Looks like the shop gave you a Bendix unit instead of a midland ross banded unit. After 69 the c body boosters were larger in diameter, and on a column shifted car the bigger booster keeps you from going into low gear on the shifter. You are better off having booster Dewey rebuild the core from Murray Park. Its the correct one for your car.

Hi there Brake experts!

Last fall I bought a Power brake conversion for my 66 Polara from Murry Park.
The kit included a power booster that I could use as a core charge.

I received a replacement BB but it is a slightly different shape than the one Murry included.

I looked up the application code for the rebuilt unit and it states it is for the Polara.

It measures up physically to the same as the core I have.

I am thinking the amount of boost I will get from the rebuilt unit since it appears to have a larger chamber.

I think I will get a little bit more duration of vacuum than the original style

The Summit Racing shows it fits as well but even Summit shows the original style with the number of the booster I received

http://www.summitracing.com/int/parts/aaz-54-73520/applications/make/dodge/year/1966/model/polara

Again, the application chart show it fits the Polara.

Have a look at the pics and let me know your opinion.

BTW: the original booster came off a "1966 Newport"

 

[bulldogchesty]

I think I had Dewey rebuild mine years ago. Works great.

 

[mr. fix it]

Interesting reply

I'm not sure how the booster would interfere with the shift linkage since the shifter comes out at the base of the steering column on the 66 Polara. .

Not to say your comment is incorrect but has me wondering.

 

[68plymouth383]

Bolt it up and try. That's what everybody has said about the 69 and newer units.

Interesting reply

I'm not sure how the booster would interfere with the shift linkage since the shifter comes out at the base of the steering column on the 66 Polara. .

Not to say your comment is incorrect but has me wondering.

 

[mr. fix it]

Btw: I am also upgrading to a dual master cylinder as well.
All the bolt contact points match up.

 

[68plymouth383]

The dual master, and single masters have the same 4 bolt pattern. The newer boosters kept the same 4 bolt pattern.
The link you posted is for the banded midland Ross. http://www.summitracing.com/parts/aaz-54-73520/applications/make/dodge/year/1966/model/polara That interchange is correct for the core Murray sent you. 1969 Dodge polara booster. http://www.cardone.com/Products/Product-Detail?productId=503500&p=rock This is the one the local re builder gave you. The 65-68 cars use 2 boosters for drum brake cars the banded midland ross that Murray gave you, and the field installed hydro-vac booster. Here's a pic of the field installed hydro-vac booster.

Btw: I am also upgrading to a dual master cylinder as well.
All the bolt contact points match up.

 

[Marian]

Looks like the shop gave you a Bendix unit instead of a midland ross banded unit. After 69 the c body boosters were larger in diameter, and on a column shifted car the bigger booster keeps you from going into low gear on the shifter. You are better off having booster Dewey rebuild the core from Murray Park. Its the correct one for your car.

I agree. The one from Murray is a Midland-Ross and period correct for your car, if that matters to you. Just send it to booster Dewey and you will be very happy you did. I'm still smiling about the BB that Matt sent me.

 

[mr. fix it]

The dual master, and single masters have the same 4 bolt pattern. The newer boosters kept the same 4 bolt pattern.
The link you posted is for the banded midland Ross. http://www.summitracing.com/parts/aaz-54-73520/applications/make/dodge/year/1966/model/polara That interchange is correct for the core Murray sent you. 1969 Dodge polara booster. http://www.cardone.com/Products/Product-Detail?productId=503500&p=rock This is the one the local re builder gave you. The 65-68 cars use 2 boosters for drum brake cars the banded midland ross that Murray gave you, and the field installed hydro-vac booster. Here's a pic of the field installed hydro-vac booster.

View attachment 26393

This looks like the unit I received.
What's the difference between the 2 units?
What is the field installed reffering to?

 

[68plymouth383]

The field installed refers to the optional boosters available for 65-68. If a car from the factory had manual brakes the dealer ship would install a field installed power brake setup at the owners request.

This looks like the unit I received.
What's the difference between the 2 units?
What is the field installed reffering to?

 

[mr. fix it]

Ok I got it now

The field installed would use the original brake pedal setup?

 

[68plymouth383]

The field installed would still be power brakes. Just with a dealer sourced booster (Field Installed) they would replace the pedal arm with a power pedal.

Ok I got it now

The field installed would use the original brake pedal setup?

 

[mr. fix it]

The field installed would still be power brakes. Just with a dealer sourced booster (Field Installed) they would replace the pedal arm with a power pedal.

Thanks for the reply it pretty much decides it then.
I will use this booster.

 

[Anthony Karbaj]

Btw: I am also upgrading to a dual master cylinder as well.
All the bolt contact points match up.

Hello, I know this is an older post but

This looks like the unit I received.
What's the difference between the 2 units?
What is the field installed reffering to?

Hello, I am looking to convert my 1966 Polara 500 383 with console shift from manual, single reservoir brakes to power with dual master cylinder. What did you end up going with on your brake conversion?
Thanks for the help
Tony

 

[mr. fix it]

Hi Tony, Welcome to the FCBO!
I would recommend using a booster from 67-68 setup if you can find this.

I used the replacement booster with all the tags on it in the picture.
You will need a Power brake pedal or weld the original hole for the pedal rod and re-drill it.
Be sure to get the correct distribution block for converting to the dual M/C setup other wise you will have a rear brake lock up issue.
(Personal experience is a great teacher)
Do not simply block off the back of the original distribution block and run the brake line to the back.
It will result in a possible rear wheel lock up.
If you go this route, you will need an aftermarket metering valve to reduce the pressure going to the back brakes.
It's a trial and error setup for the first bit but once set, you shouldn't have to touch it again
Here is a Wilwood link but there are others out there.
Wilwood Disc Brakes - Porportioning Valves & Pressure Valves

Lastly, be sure to plumb the MC lines so the rear chamber feeds the front brakes & the front chamber feeds the rears...

 

[Mike66Chryslers]

The brass distribution block for drum brakes was just a distribution block, not a metering/proportional valve. You only need one of those if changing to front disc brakes. The only thing that's special about the 1967+ distribution block for drum/drum setups is that it incorporated a switch to detect if one circuit failed to illuminate the brake warning light on the dashboard.

My brother and I have converted two 1966 Chryslers with 4-wheel drum brakes to the 1967+ dual reservoir MC's without changing the distribution block and not had any braking problems.

 

[mr. fix it]

The brass distribution block for drum brakes was just a distribution block, not a metering/proportional valve. You only need one of those if changing to front disc brakes. The only thing that's special about the 1967+ distribution block for drum/drum setups is that it incorporated a switch to detect if one circuit failed to illuminate the brake warning light on the dashboard.

My brother and I have converted two 1966 Chryslers with 4-wheel drum brakes to the 1967+ dual reservoir MC's without changing the distribution block and not had any braking problems.

Hi Mike.
Have you ever had to do a hard brake application?
You will not notice the problem under light braking.

I had used the original distribution block to feed the fronts. blocked off the rear port and fed the rear brakes from the MC directly following what most members stated they had done..

I only found out when I had to do a panic stop and the rear of the car tried to come around on me.
Once I added a distribution block from a 67 Polara the problem was solved.

Maybe the MC you have used had a metering valve built in? I confess I had a B/N Chinese unit from AZ.
This may have been the cause for my rear wheel skid.
Again the addition of the correct DB solved my problem.

 

[Zymurgy]

I was so confused now I see the original post date.

 

[Mike66Chryslers]

Hi Mike.
Have you ever had to do a hard brake application?
You will not notice the problem under light braking.

I had used the original distribution block to feed the fronts. blocked off the rear port and fed the rear brakes from the MC directly following what most members stated they had done..

I only found out when I had to do a panic stop and the rear of the car tried to come around on me.
Once I added a distribution block from a 67 Polara the problem was solved.

Maybe the MC you have used had a metering valve built in? I confess I had a B/N Chinese unit from AZ.
This may have been the cause for my rear wheel skid.
Again the addition of the correct DB solved my problem.

The drum MC is supposed to have residual pressure valves on both the outlet ports to retain some line pressure. Disc brakes do not use a residual pressure valve. Possibly your MC does not have residual pressure valves and your prop valve is compensating for that somehow? A friend of mine once gave me a freshly reman drum/drum MC because it didn't have the residual pressure valves installed. I took it to a brake system rebuilders and they just gave me a couple to install myself.

I tested locking up the brakes right after doing the dual-reservoir MC conversion on my convertible. My brother had plumbed it in for me and when I saw it I said he had plumbed the front and rear circuits into the wrong ports. We went out and tested it, then swapped the lines into the correct ports and retested it.

I also converted my other Chrysler to front discs and plumbed in an aftermarket prop valve. I road tested that to get the prop valve set correctly.

 

[mr. fix it]

That’s likely what happened then with my MC