Disc Brakes for an Imperial

macr0w

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So, let me ask this question: Is the biggest problem with available disc conversions that the only available parts that will work give you the wrong lug pattern?
I read a couple posts about the spindle height.
What the deal with the Dodge truck rotors I read about?
I'm just trying to get it straight here. :confused:
 

CBODY67

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Other than "spindle height" (especially how "tall" they might be when compared to the drum brake items!!!), the main issues are the size of the ball joint studs and how the caliper mounts will or CAN interface with the caloper mounting items. PLUS how the ball joint locations might also affect front end steering geometry. THEN there are the particular wheel bearings (inside and outer diameters, etc.) and how THEY interface with the brake rotors and the spindles. After all of those things are figured out, THEN comes the wheel bolt pattern.

As I understand it/suspect, the pre-1967 Imperial chassis items probably reflect a lot of the 1957 engineering and design orientations. Possibly even some prior "Forward Look" parts, too. Which, if you watch the "On The Test Track with the 1957 Chryslers and Imperial" videos on YouTUBE, is not that shabby!! Add-in the allegedly better tires we have now and it can become evey better, too.

ONE key item in brake performance is the type and quality of the linings. It seems that www.musclecarbrakes.com allegedlhas the best linings in their products. Perhaps they might reline your existing shoes with their better linings?

Booster Dewey is usually the go-to person/entity for power brake booster rebuilds. Not that you can't do it yourself, but allegedly there can also be some safety liability issues involved too. Good reviews from the related www.forbbodiesonly.com forums? There are some things which it is usually better for "other known reliable entities" to do rather than DIY, by observation.

Just some thoughts,
CBODY67
 

GoneLoco99

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I too would like to switch my ‘68 Imperial rear drum brakes over to disc brakes.
 

Big_John

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Thanks Big_John, that is an interesting read.
I think I'm going to look into either rebuilding or replacing the booster and master cylinder and see what we get.
Does anyone know if this kit from Pirate Jack is worth buying or not?
Mopar Bendix Style Power Brake Booster, Drum Drum Master Cylinder | eBay

He says it will fit a 65 Imperial.

First and foremost, never, never, never, go by eBay listings for fit and/or capability with your car. I've seen a lot of incorrect listings and more than one person here has gotten burnt by buying what they thought were the right parts based on eBay listings.

Next, the MC would be the one you want, but I don't know about the booster. Will it bolt up? Yea, the bolt pattern is the same... Will it really fit? No idea, probably not well enough.

So, a couple things... If you really want to do a conversion, this isn't the MC you want anyway... If you want to stay with drums, yep, that's it.

Next, and this should have been asked... What's wrong with the drums on your car now? Some scoring is OK... Drums often get turned or replaced for really no good reason. Do you really need to replace the drums?

If you want to do the conversion, I get it... Disc brakes are what "everyone does", but really the drum brakes on your car are pretty beefy and as long as they are good, the braking won't really be that much better. Gotta remember why that Detroit started putting disc brakes on everything because they are cheaper... Yes, they have an advantage in fade resistance, but you aren't going to be autocrossing the Imperial either, so multiple hard stops aren't going to be happening.

Now, nothing wrong with disc conversions, although a lot of the kits don't impress me. It is a good upgrade, if done correctly, but it isn't as necessary as some seem to think. Most guys that rave about the better braking were going from a shitty, worn out brakes to new disc stuff and IMHO, it's really comparing apples to oranges. Quite frankly, IMHO, a lot of the mods I see are done to band-aid bad repairs, but I digress.

So, my advice is to look at what you have, buy some good, maybe NOS shoes and do whatever repairs to the rest. Booster Dewey is the go to for rebuilding the booster if it needs it. Converting to a dual MC is a very good option and I encourage you to do that. I've done that one (dual MC) myself a couple times... The last dual MC I did is to my '65 Formula S Barracuda, which still has it's drum brakes... and stops just fine.
 

CBODY67

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@Big_John is highly accurate in his assessments.

In doing any brake job, the normal procedure is to have perfectly smooth and flat surfaces for the frictions to rub against. "No pull, no brake pedal pulsations", BUT if there were no brake pulsations to start with and the surfaces were not gouged/grooved, then no real reason to cut the drums, from my experiences. It might take a little bit longer for the shoes to get "mated"/worn-in on those surfaces, but when that's done, then there can be marginally MORE actual braking surface for the frictions to work with. But every mechanic/DIY-er wants things to be "the best" as soon as the job is completed. NO problem with that, except that "the best" only happens after the frictions have gotten hot a few times from use, i.e., "break-in". Take ANY fresh brake job out and nail the brakes to test them under emergency situations and in many cases, they will NOT stop straight, nor will they ever stop straight consistently after that, by observation. IF the friction surface on the drums or discs is NOT to OEM cut/ smoothness specs, then things can get worse, too, by observation. End result, in some cases, all of these "make it the best" activities can actually make things worse. These things used to be known years ago, to advise the customer to use "easy stops" for the first several stops, which can be done, but NOT to go out and do any emergency situation stops for a while, unless condititions dictate such.

ONE thing about new drums is that they might well need to be "cut", depending upon how the box they were in was stored on the shelf. If stored vertically, they'll probably have a bit of an oval shape to them. If stored horizontally, most probably they will be round. The vertical storage can result in brake pedal pulsations, too, so best to put some miles on them before they are machined round. Not unlike how a seasoned engine block is better to machine than a new/"green" engine block.

Now, there is a procedure to "break-in"/"wear-in" new brake shoes and pads. Something like 10 easy stops from 45mph, followed by a complete cool-down before 10 moderate stops from 60mph, followed by a complete cool-down. This heats the friction material to "cook-out" any gasses in the "green"/new friction materials. Should the drum/disc contact surfaces be too rough and do not have the "non-directional polish" on them, the rougher surface will cause the frictions to heat and fade much quicker, by observation. So, NO panic stops until all of these things are completed, for best results and long-lasting braking performance, from my own experiences.

Disc brakes do have better fade resistance than drum brakes by design. But a drum brake system with quality frictions can be a better-stopping system than a disc brake system with poor-quality frictions, even in the fade resistance criteria. But with federal standards and such, this can be less of a concern than it was in the middle 1960s, by observation.

Sorry for the length. Many thoughts and experiences,
CBODY67
 

macr0w

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Thanks for the input guys.
I agree with what you are saying.
I'm not hell bent on disc for this car. As my son and I are new this car I was hoping it would be easier.
I think we are going to get a new dual master cylinder and talk Dewey about a booster rebuild and see what the drums look like.
Where can I get brake shoes/pads for this thing?
 

detmatt

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Thanks for the input guys.
I agree with what you are saying.
I'm not hell bent on disc for this car. As my son and I are new this car I was hoping it would be easier.
I think we are going to get a new dual master cylinder and talk Dewey about a booster rebuild and see what the drums look like.
Where can I get brake shoes/pads for this thing?
@mobileparts
 

mobileparts

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You are 100 % correct as usual, Matt / detmatt...
Spent last seven (7) days at Fall Carlisle --- and will be at HERSHEY for the next six (6) days....

I P.M.ed him.... Thank You.... yours, Craig....
 

mobileparts

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I only received a P.M. from boydsdodge yesterday.....
And I received absolutely NO communication from this macr0w, at all, period, and my inbox now has all 15 messages in there, and I can not erase / delete them --- but the 15th was boydsdodge yesterday.....

Yours, Craig....
 

macr0w

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I only received a P.M. from boydsdodge yesterday.....
And I received absolutely NO communication from this macr0w, at all, period, and my inbox now has all 15 messages in there, and I can not erase / delete them --- but the 15th was boydsdodge yesterday.....

Yours, Craig....
Okay :confused:
 

CBODY67

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1965 Chrysler FSM indicates 11x3 f/r brake shoes for the '65 Imperials.

Drum brakes have "brake shoes" as disc brakes have "brake pads", FWIW

Enjoy!
CBODY67
 

macr0w

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I only received a P.M. from boydsdodge yesterday.....
And I received absolutely NO communication from this macr0w, at all, period, and my inbox now has all 15 messages in there, and I can not erase / delete them --- but the 15th was boydsdodge yesterday.....

Yours, Craig....
I did send you a message btw. :confused:

Mobile Parts.JPG
 

macr0w

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1965 Chrysler FSM indicates 11x3 f/r brake shoes for the '65 Imperials.

Drum brakes have "brake shoes" as disc brakes have "brake pads", FWIW

Enjoy!
CBODY67
I see in my fsm that the shoes are 11"x3".
Does that mean that any brake shoe that has a surface of 11"x3" will work?
I put up a link to some at Rock Auto the other day.
Rock Auto says they'll fit. I was just curious what people do for brake shoes.
That seems like a consumable item that people would need to replace every so often.
Surely there's more than just a nos or used market for brake shoes, right?
Can they be bought new?
 

Big_John

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I see in my fsm that the shoes are 11"x3".
Does that mean that any brake shoe that has a surface of 11"x3" will work?
I put up a link to some at Rock Auto the other day.
Rock Auto says they'll fit. I was just curious what people do for brake shoes.
That seems like a consumable item that people would need to replace every so often.
Surely there's more than just a nos or used market for brake shoes, right?
Can they be bought new?

It's complicated... LOL.

Some of the issue revolves around the friction material. In 1993, no one was supposed to be making asbestos based brakes in the US. By 1997, no one is supposed to be selling asbestos and federal law even specifies that asbestos brake shoes are not even supposed to be on the shelf.

Somewhere in the 80's asbestos was being phased out in new cars and the larger aftermarket companies.

I personally think most of the issue is the general quality of the imported brake shoes.

So, the thought is to find older, NOS or NORS brake components for the better quality. The problem is always finding them for a reasonable price and I'm always suspect of some of these NOS parts... Are they really authentic? But that's another subject.

I've always found what I needed by using part numbers and searching eBay, getting away from the overpricing that some vendors charge. Of course the issue is figuring out the superseded part numbers, so I have to do a little homework, but that's usually just a matter of some searching.

So, will the Rock Auto stuff work? Yep... It will stop the car and probably as good as any of them. My experience with Centric brake shoes (long story, came with the car) was a lot of brake dust and noise. Will the NOS shoes perform better? Well, they will perform as the car was supposed to when new. Probably wear a little longer, although how many miles are you going to drive your Imperial?

But, it really comes down to this question... Do you need to replace any of this stuff? Is everything still working? Pulling it apart for inspection is really recommended and I really would recommend doing the dual MC conversion... But have you looked at what's on the car now?
 

macr0w

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The reason I'm asking these questions and looking at all options is because:
#1 this car belongs to my 17 year old son and he is the primary driver.
#2 the existing single pot master cylinder should be changed out just for safety.
#3 the brakes as they are have almost no pedal, no return, the drivers side front locks up. It will change lanes on you.
#4 when you put your foot on the pedal while rolling the front end shimmies like crazy.
It's not safe in my opinion.
At the least it needs taking apart and repairing.
I'm just trying to figure out where I can find parts and what options are available before I do.
 

CBODY67

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In the world of brake friction parts, drum and disc, there are "industry numbers" which usually are a part of ANY brake manufacturer's part number. For example, "D52" is a common Chevy/GM power front disc brake pad set. No matter who made the pads, in the aftermarket, that "D52" is in their part number somewhere, usually in the middle surrounded by various other letters which denote the manufacturer and lining material, by observation.

The Chrysler 11x3 brake shoes were used for many years, especially on C-body station wagons, police cars, and many front power drum brakes on things like Plymoutyh GTXs. As I recall, the front and rear brake shoes are the same, front and rear, for the 11x3 f/r cars?

Look in the online catalogs of Raybestos and Wagner brake parts if the Rock Auto listings might get a bit blurry. Check out the Dynamic Friction catalog, too, for good measure. The easiest way to get into their catalogs is to click on their logo in the lh upper corner of the Rock Auto page which comes up when you click on "INFO" in their listings.

It seems that the 11x3 shoes are easy to find, but drums might be a bit more difficult. Another place where the RockAuto catalog might yield several options.

Be sure to get new hardware packages, too. Plus wheel cylinders AND the rubber brake hoses (frt & rr).

It's my understanding that any brake friction sold in the USA is supposed to meet FMVSS specs for basic performance and pedal pressure needed to make them work like the factory brakes did when the cars were new. Consider that "minimum spec" rather than "maximum spec", though. FWIW

Just some thoughts,
CBODY67
 
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