Upgrading from kelsey hayes to???

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Kennkenniff

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Wondering if anyone has or knows about mounts to put late model viper or brembo calipers onto a 72 demon that already has the kelsey hayes disk brakes, ive searched everywhere but it always leads back to swapping from drum to disk and im hoping to keep all my 72 sbp front end parts and just upgrade to better calipers, also I have access to a milling machine so making my own brackets is an option, really just need to find the best caliper for the job and was hoping someone has done this before..

Thank you in advance
Ken P
 
How big of a wheel would you need to make the late model calipers work?
 
Most use the 73 knuckles. Not sure why you would bother if you have K-H discs. Have you tried better pads?
 
That Demon has huge wheelwells in the back. Like my 68 Barracuda.
I installed 235/60-14s on the front with the same brakes as yours. On the back I installed 295/50-15s. With 10 x 2 drums, and NO proportioning whatsoever, and some big W/Cs back there. Now the back brakes awesomely, and I don't have to lock up the fronts anymore.
But to be fair, My driving is 100% street,
and ~99.9% of it, is at less that 65mph/5600rpm.
Second gear tops out at 6500=75mph, to 7200=84.lol
 
Most use the 73 knuckles. Not sure why you would bother if you have K-H discs. Have you tried better pads?
The calipers that came with car hadn't been touched in years and will need a rebuild, so I figured instead of spending any money on rusty old junk I'd spend a few extra bucks and put high performance parts if there's an option to retain my existing parts and put a bracket and better calipers, by the sounds if it i will need to find a performance caliper that fits and make the brackets myself, I was just hoping someone could steer me towards the best calipers to take the k/h place
 
That Demon has huge wheelwells in the back. Like my 68 Barracuda.
I installed 235/60-14s on the front with the same brakes as yours. On the back I installed 295/50-15s. With 10 x 2 drums, and NO proportioning whatsoever, and some big W/Cs back there. Now the back brakes awesomely, and I don't have to lock up the fronts anymore.
But to be fair, My driving is 100% street,
and ~99.9% of it, is at less that 65mph/5600rpm.
Second gear tops out at 6500=75mph, to 7200=84.lol
295s in the back is awesome I thought the biggest was 275, ive started the process of moving the wheelhouses into the frame rails, my car strangely came with the springs relocated but not the mini tubs, thanks for the Info my friend.
 
How big of a wheel would you need to make the late model calipers work?
My hope was by using the stock K/H disks i wouldn't have to worry to much about wheel selection, I know some late model buicks/cadillacs came with brembo calipers on all 4 wheels so im going to have to do some research on all this stuff and see if its worth doing, my car currently has centerline skinnies on the front and I dont see them staying, theres a guy locally that's started making custom sized rims to accommodate chevy poverty caps/dog dish and ive heard he has made a couple sets of mopar rims aswell
 
These use a 13.6 rotor but If they could function with an 11 inch stock rotor I'd be happy, Im just guessing here i have no clue about how this all works when it comes to calipers, im assuming there designed specifically to work with a 13.6 rotor, but i wonder if there's any side effects to adapting them to work clamping a 11" rotor

Screenshot_20210121-161243_eBay.jpg
 
The calipers that came with car hadn't been touched in years and will need a rebuild, so I figured instead of spending any money on rusty old junk I'd spend a few extra bucks and put high performance parts if there's an option to retain my existing parts and put a bracket and better calipers, by the sounds if it i will need to find a performance caliper that fits and make the brackets myself, I was just hoping someone could steer me towards the best calipers to take the k/h place

If you have them rebuilt with brass sleeves and stainless steel pistons you will be good for another 50 years with DOT 5 fluid. They are 4 piston fixed calipers. Very comparable to Willwood and others. As a system, they are light, and since they use the same brake pads as vintage Mustangs and Vettes, there is a good selection. Costly? Yes, but the complication factor is nil. I have a complete Viper caliper set up in a tote and don't feel the need to upgrade either of my 2 Barracudas yet. Your money and car.
 
OP,
You got me seriously confused;
You are in the Forum called
Brakes for your Classic Mopar

Why do you want race brakes on street tires? You already have more brakes (KH) on your car than even 235s can handle, and 235s are about the biggest you can install without incurring steering issues, until you go to 17/18 inch rims. I hope yur not letting your Chevy buddies spend your money........

295s fit into my 68 Barracuda tubs no problem, with the springs moved over. I even lowered the car down over them. My tubs actually accepted 325/50-15s on 10" rims, at the factory height, with just a lil sheetmetal adjustments.



 
If you have them rebuilt with brass sleeves and stainless steel pistons you will be good for another 50 years with DOT 5 fluid. They are 4 piston fixed calipers. Very comparable to Willwood and others. As a system, they are light, and since they use the same brake pads as vintage Mustangs and Vettes, there is a good selection. Costly? Yes, but the complication factor is nil. I have a complete Viper caliper set up in a tote and don't feel the need to upgrade either of my 2 Barracudas yet. Your money and car.
Ok thank you, can you reccomend anywhere to buy the brass sleeves and stainless pistons? I've never drove the car so I have no idea about how the brakes perform, but ive read alot of comments across the web with people saying the K/H are weak and can be spongey, it does sound like doing a rebuild myself and adding some braided lines and quality pads and it should stop as good as one can expect from a 50 year car and not cost me more than a couple hundred bucks, for me the car is a h code 72 demon that's a complete basket case I will be touching every inch of it and I dont have the build sheet or fender tag, so making it original is the last thing im going to worry about, im just in the process of getting as much of the missing parts I can find for assembly after I get it back from paint,
OP,
You got me seriously confused;
You are in the Forum called
Brakes for your Classic Mopar

Why do you want race brakes on street tires? You already have more brakes (KH) on your car than even 235s can handle, and 235s are about the biggest you can install without incurring steering issues, until you go to 17/18 inch rims. I hope yur not letting your Chevy buddies spend your money........

295s fit into my 68 Barracuda tubs no problem, with the springs moved over. I even lowered the car down over them. My tubs actually accepted 325/50-15s on 10" rims, at the factory height, with just a lil sheetmetal adjustments.
Thank you captain obvious for telling me where I posted this post, you have done me a great justice, to keep you from becoming more confused ill explain, I did not say I wanted "race" brakes i specified that I was curious if there is any options to put better calipers on my car instead of rebuilding the worn out K/H calipers it has and if there was a bracket to adapt a "performance" brake caliper to the
OP,
You got me seriously confused;
You are in the Forum called
Brakes for your Classic Mopar

Why do you want race brakes on street tires? You already have more brakes (KH) on your car than even 235s can handle, and 235s are about the biggest you can install without incurring steering issues, until you go to 17/18 inch rims. I hope yur not letting your Chevy buddies spend your money........

295s fit into my 68 Barracuda tubs no problem, with the springs moved over. I even lowered the car down over them. My tubs actually accepted 325/50-15s on 10" rims, at the factory height, with just a lil sheetmetal adjustments.
So what exactly has you confused? It doesn't say classic brakes for a classic mopar?? Guys like you make me realize why the entire classic car community thinks mopar guys are serial killers, the thing thats awesome about building a classic custom car is, its my car and I can build it how ever I want it! And theres always going to be some oldhead purist who has all the money in the world to restore his toys that gets "confused" when someone does something different
 
Those little old brakes were pretty good, so be careful what you call an upgrade.
 
295s in the back is awesome I thought the biggest was 275, ive started the process of moving the wheelhouses into the frame rails, my car strangely came with the springs relocated but not the mini tubs, thanks for the Info my friend.

275's on a Duster/Demon is the most you'll do without moving the springs over at least a 1/2". I run 295's on my Duster, but that took a 1/2" spring offset and another 1/2" trimmed off the quarter lips to keep them from rubbing.

Without the mini-tubs the 3" relocation doesn't buy you any more than a 1/2" offset, so if you've got a 3" relocation and stock tubs you could likely run 295's as well as long as the backspace was right.

My hope was by using the stock K/H disks i wouldn't have to worry to much about wheel selection, I know some late model buicks/cadillacs came with brembo calipers on all 4 wheels so im going to have to do some research on all this stuff and see if its worth doing, my car currently has centerline skinnies on the front and I dont see them staying, theres a guy locally that's started making custom sized rims to accommodate chevy poverty caps/dog dish and ive heard he has made a couple sets of mopar rims aswell

This I don't understand. You want to run Viper calipers on stock SBP rotors with SBP wheels? The Viper calipers are huge, the odds of them clearing a stock rim is about nil even if you use factory rotor. Which you can't. The Viper calipers use a 1.25" thick caliper. And there's no kit available that I'm aware of that puts them on anything smaller than a 13" rotor. A 13" BBP rotor, I might add, because you'll need at least 17" wheels to clear them.

If you want to keep your stock wheels, then I would just rebuild the calipers. The KH calipers are actually pretty decent for braking power, even if they do have some seal/leak issues.

If you want Viper calipers, you need to change a lot more than just the calipers to make it work. Even if you make your own caliper brackets I think you'll have issues with those gigantic Viper calipers clearing anything resembling a factory wheel.
 
Stainless Steel Brake Co got their start in upgrading K-H calipers w/ stainless pistons that wouldn't corrode and jam. The main market was Mustang, but the Mopar A-body calipers are very similar. I think they are still in business selling better calipers or refurbing them. I recall another company which made calipers to fit your disk spindles, with an aerospace name, and recall seeing them still in business. Haven't been there, just looked at disk brake option long ago for my 1965 Dart, so don't quote me or flame me.

Yes, some people get ticked off here. One thing I try to point out that really upsets some is that brakes don't stop the car, tires do. If the brakes can stop the wheel from turning, that is sufficient and no bigger brakes can do anything more. Of course you don't want to skid the tires, but brake to the point just before they skid (or pump pedal if they skid). If repeated braking from high speed, then larger rotors and pads can dissipate the heat faster to avoid pad fade (melting), but that is only needed for road-racing on twisty turns or for those dumb enough to "ride the brakes" on a long downhill grade.
 
Stainless Steel Brake Co got their start in upgrading K-H calipers w/ stainless pistons that wouldn't corrode and jam. The main market was Mustang, but the Mopar A-body calipers are very similar. I think they are still in business selling better calipers or refurbing them. I recall another company which made calipers to fit your disk spindles, with an aerospace name, and recall seeing them still in business. Haven't been there, just looked at disk brake option long ago for my 1965 Dart, so don't quote me or flame me.

Yes, some people get ticked off here. One thing I try to point out that really upsets some is that brakes don't stop the car, tires do. If the brakes can stop the wheel from turning, that is sufficient and no bigger brakes can do anything more. Of course you don't want to skid the tires, but brake to the point just before they skid (or pump pedal if they skid). If repeated braking from high speed, then larger rotors and pads can dissipate the heat faster to avoid pad fade (melting), but that is only needed for road-racing on twisty turns or for those dumb enough to "ride the brakes" on a long downhill grade.

Once again, this ignores impulse forces and the difference between static and dynamic friction coefficients. Rolling and sliding friction coefficients are different.

You can lock the wheels up with a quick stab of even fairly small brakes. That does not mean that your brakes are adequate, or that you wouldn't stop faster with better or larger brakes. You can slow the car much faster if the wheels stay turning, and that requires MORE brake force than what it does to just lock the wheels with a quick stab.

It's true, all the braking force has to go through the tires. Better tires do result in better stopping as long as the brakes can take advantage of the additional traction. But you can lock the wheels up with a pair of crappy 9" drums. They're still abysmal brakes, and their ability to lock up the wheels does not prove their worth. Just because they can lock the wheels doesn't mean better/larger brakes won't stop the car faster. They do, and the physics of friction coefficients explain why. That's before you even consider heat dissipation.

Sure, there's no reason to run giant calipers and rotors if you're going to run hard compound, skinny tires. The tires are only capable of so much. But the ability of a brake to lock the wheels is not at all a good measure of its capability, there's can be a big distance between locking the wheels up and using up every bit of rolling friction a tire can provide.
 
Hydraulics is hydraulics is hydraulics!
Spongy brakes are generally due to leaks, a bad master cylinder or improperly sized master cylinder.
For comparison, I have a '37 Pontiac street rod with an original '74 Mustang II front clip, weighs 3800 pounds. I upgraded the original 9" discs to 11" GM metric discs & calipers along with a 9" dual diaphram power booster. Stops on a dime with little effort, almost too much power assist!
My '64 Valiant has the KH conversion with a manual MC. It stops just as well, with just a bit more pedal effort due to the manual MC.
The only way to upgrade braking performance, if it's actually needed, is to get better pads and/or increase swept braking area (contact) which means larger discs. I don't think you would see significant gain in swept area by just changing calipers.
 
This is the best I could find for caliper rebuilding. Go stainless steel pistons for sure. I remember seeing someone who professionally rebuilt calipers and used brass sleeves. Maybe it is not necessary with cast iron and stainless steel pistons. Mine were done decades ago with stainless sleeves and stainless pistons. Original Kelsey Hays disc master cylinders were 1.000 bore for manual and power.

Brake Sleeving & Rebuilding Services – White Post Restorations

Calipers Online
 
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That would be ;
Mr. Captain Obvious ,to you, but, Ok since yur a newbe, I'll let your arrogance slide.
Back to business.

There is NOTHING wrong with the KH brakes.
I have been running them on all my Classic Mopars, semi-continuously, since 1970. Including on one of the worst handling Mopar A-body combos of all time; the 70DartSwinger 340/4-speed on E70-14 Poly-glass tires.
That's 50 years; and during all those years, I have never had even one accident ever, attributable to braking. On the street, if you need more brakes, you don't really know how to drive, or your tires are junk, or yur just not paying attention. Don't blame the brakes. There is only one thing discs do better than drums; namely get rid of heat better. So they can take the abuse of multiple stops, in a short period of time ........ like in racing.

None of my KH calipers have ever been sleeved, and I have been running the Silicon fluid since it came out.

On the street, in the back, once you re-engineer your proportioning for your tires, 10x2 drums are more than adequate, . I went heavy in the back, and change my rear shoes between two and three times as often as the front pads. Those 295s in the back are like throwing out a parachute.
But even with those big contact patches back there, when sliding sideways, the rear brakes can do exactly nothing but make it worse. So that's where over 50 years of driving experience comes in handy.

BTW I'm no purist
My 68 Barracuda was originally a /6-auto. Today, it has a 71 360 in it, with a 64/65 Commando 4-speed, a GVod and 3.55s from about 71, in a narrowed 70 housing. The heads are alloys from 1999,as is the intake. The 750DP is older than probably you are. The Distributor had beem cobble together from so many different year parts, even JohnnyCash couldn't make up a song about it. The headlights are halogen, in 70's tech reflectors, cuz IMO, there's nothing better.The front brake system came off a 70Duster, the steering off a 73, the suspension is PST with a big solid bar and 1.03 T-bars. The shockks ar ancient 3-way Munros. The 70 Duster also donated it's Rally Dash with it's 150mph Speed-O, and the Dashpad is from a 69 Barracuda. The buckets are from an old RX-7, The shifter is a 1971 Mr.Gasket Bang!
The rods are from a 318, the crank is 1971 the KB107s were new in 1999. The valve gear is circa the 70s, as is the front of the motor except the pump is a Milodon, like the pan, circa 2001. I think I installed the AirGap in about 2002. The camkit is a Hughes from 2004.
I finally deleted the horns cuz I kept wearing them out, and so I learned to drive in an area where there don't seem to be any driving rules. Which works both ways cuz I like to slide around corners and punch it over speed bumps, that tuner-cars are crabbing over. I drive my Barracuda on gravel too, and on dirt, including an occasional jump, now that I fabricated a belly-pan for it.
The only thing purist about me is that I have been married and faithful, since 1977. So bite your lips and suck back your talons.
I don't care what brakes you run or how many G-bills you shell out to get them fitted; as long as you run the same tires, your street stopping distance is not likely to change much if at all, unless it gets longer, cuz you locked 'em up worse, cuz your head was still grumbling.
I was trying to save you hassles, time, and money. But you turned it into an opportunity to grumble. Fair enough, the world is full of grumblers.
 
Now we're talking! This is exactly why I started this thread! I wanted the guys who know about brakes to share some the precious info you guys store in your brains.
 
Hydraulics is hydraulics is hydraulics!
Spongy brakes are generally due to leaks, a bad master cylinder or improperly sized master cylinder.
For comparison, I have a '37 Pontiac street rod with an original '74 Mustang II front clip, weighs 3800 pounds. I upgraded the original 9" discs to 11" GM metric discs & calipers along with a 9" dual diaphram power booster. Stops on a dime with little effort, almost too much power assist!
My '64 Valiant has the KH conversion with a manual MC. It stops just as well, with just a bit more pedal effort due to the manual MC.
The only way to upgrade braking performance, if it's actually needed, is to get better pads and/or increase swept braking area (contact) which means larger discs. I don't think you would see significant gain in swept area by just changing calipers.
Thank you! Your pontiac sounds pretty cool, I recently gave my dad a 1930 desoto 8 sedan that was in finish assembly after a frame off restoration and he decided to street rod it, its in the process of having a modern hemi and bolt in mustang 2 front end system, Ill likely just rebuild the calipers I have, it seams like most of these aftermarket kframe/coil over suspension systems sold for abodes are just a modified version of the mustang 2 front end.
 
That would be ;
Mr. Captain Obvious ,to you, but, Ok since yur a newbe, I'll let your arrogance slide.
Back to business.

There is NOTHING wrong with the KH brakes.
I have been running them on all my Classic Mopars, semi-continuously, since 1970. Including on one of the worst handling Mopar A-body combos of all time; the 70DartSwinger 340/4-speed on E70-14 Poly-glass tires.
That's 50 years; and during all those years, I have never had even one accident ever, attributable to braking. On the street, if you need more brakes, you don't really know how to drive, or your tires are junk, or yur just not paying attention. Don't blame the brakes. There is only one thing discs do better than drums; namely get rid of heat better. So they can take the abuse of multiple stops, in a short period of time ........ like in racing.

None of my KH calipers have ever been sleeved, and I have been running the Silicon fluid since it came out.

On the street, in the back, once you re-engineer your proportioning for your tires, 10x2 drums are more than adequate, . I went heavy in the back, and change my rear shoes between two and three times as often as the front pads. Those 295s in the back are like throwing out a parachute.
But even with those big contact patches back there, when sliding sideways, the rear brakes can do exactly nothing but make it worse. So that's where over 50 years of driving experience comes in handy.

BTW I'm no purist
My 68 Barracuda was originally a /6-auto. Today, it has a 71 360 in it, with a 64/65 Commando 4-speed, a GVod and 3.55s from about 71, in a narrowed 70 housing. The heads are alloys from 1999,as is the intake. The 750DP is older than probably you are. The Distributor had beem cobble together from so many different year parts, even JohnnyCash couldn't make up a song about it. The headlights are halogen, in 70's tech reflectors, cuz IMO, there's nothing better.The front brake system came off a 70Duster, the steering off a 73, the suspension is PST with a big solid bar and 1.03 T-bars. The shockks ar ancient 3-way Munros. The 70 Duster also donated it's Rally Dash with it's 150mph Speed-O, and the Dashpad is from a 69 Barracuda. The buckets are from an old RX-7, The shifter is a 1971 Mr.Gasket Bang!
The rods are from a 318, the crank is 1971 the KB107s were new in 1999. The valve gear is circa the 70s, as is the front of the motor except the pump is a Milodon, like the pan, circa 2001. I think I installed the AirGap in about 2002. The camkit is a Hughes from 2004.
I finally deleted the horns cuz I kept wearing them out, and so I learned to drive in an area where there don't seem to be any driving rules. Which works both ways cuz I like to slide around corners and punch it over speed bumps, that tuner-cars are crabbing over. I drive my Barracuda on gravel too, and on dirt, including an occasional jump, now that I fabricated a belly-pan for it.
The only thing purist about me is that I have been married and faithful, since 1977. So bite your lips and suck back your talons.
I don't care what brakes you run or how many G-bills you shell out to get them fitted; as long as you run the same tires, your street stopping distance is not likely to change much if at all, unless it gets longer, cuz you locked 'em up worse, cuz your head was still grumbling.
I was trying to save you hassles, time, and money. But you turned it into an opportunity to grumble. Fair enough, the world is full of grumblers.
I apologize if I came across as grumbling, but these online forums and Facebook groups are infested with guys who go out of there way to add there stubborn 2 cents, when in reality these "newbie" and younger guys getting into your 50 year hobbies is what keeps it alive and keeps the demand for used parts and keeps alot of people in business, im 40 years old and out of let's say 20 of my close pals theres 2 of us that care about keeping these old cars alive and as the years click by less and less of the younger generation want to do anything other than play video games and drive a fuel efficient kia, so the reality to it is, newbies should be welcomed with open arms, since joining this page ive bought thousands of dollars worth of parts from many members here and will continue to, and im sure alot of the other young blood could say the same, so all im asking is lighten up and get used to guys who have no clue about the flux capacitor you have 4 of on your garage shelf and be helpful instead of "confused".
 
There is NOTHING wrong with the KH brakes.
I have been running them on all my Classic Mopars, semi-continuously, since 1970. Including on one of the worst handling Mopar A-body combos of all time; the 70DartSwinger 340/4-speed on E70-14 Poly-glass tires.
That's 50 years; and during all those years, I have never had even one accident ever, attributable to braking. On the street, if you need more brakes, you don't really know how to drive, or your tires are junk, or yur just not paying attention. Don't blame the brakes. There is only one thing discs do better than drums; namely get rid of heat better. So they can take the abuse of multiple stops, in a short period of time ........ like in racing.

None of my KH calipers have ever been sleeved, and I have been running the Silicon fluid since it came out.

On the street, in the back, once you re-engineer your proportioning for your tires, 10x2 drums are more than adequate, . I went heavy in the back, and change my rear shoes between two and three times as often as the front pads. Those 295s in the back are like throwing out a parachute.
But even with those big contact patches back there, when sliding sideways, the rear brakes can do exactly nothing but make it worse. So that's where over 50 years of driving experience comes in handy.

Disk brakes do a lot more than just dissipate heat better. They also work better in wet conditions. And there's no clunky star wheels or adjusters, you always get the same braking. One click on the old star wheel because you backed up around a corner and suddenly one of the rears locks and the other doesn't. Been there.

And disk brakes work better than the drums, even on the rears. I've posted this article before, there are others like it. Mopar muscle did a rear disk conversion on a '73 Dart Sport and checked the stopping distances between the rear drums and rear disks from 60-0. Their result was that from 60 mph factory disks up front and factory drums in the back the car took 133 feet, 6 inches to stop. After the rear disk conversion, the stoping distance improved to 122 feet 4 inches. That's 11 feet, and that's just replacing the REAR drums with disks. Which should be less than 30% of your braking to begin with.

The online article is a total mess now, probably something with being converted over or moved to Hot Rod when MM was bought out. The final distance used to be a caption on the second to last picture, but I don't see the captions popping up anymore. I have the hardcopy article so I can attach that info. It doesn't ever say what size tires are on the car, but they're BFG T/A's. Rears are taller and wider than the front, which no doubt is part of why the rear disks made such a big difference. But that should tell you something. If you're running wide rear tires, you can do A LOT better than 10"x2" drums. That car doesn't have 295's on it. Maybe not even 275's.

Rear Disc Brakes - All Bound Up - Mopar Muscle Magazine
IMG_0115.jpeg


How lousy are factory drums and bias plys? Real lousy.

Here's a Road Test Report on a '71 340 Demon, drum/drum car. The stopping distances were absolutely abysmal, for anyone that says drum/drum is ok on the street today. The Road Test guys said they expected a 60-0 of 155 to 165 feet. What they actually got was a stopping distance of 169 ft, on a 3,250 lb car with E70's. That was their "best" distance, not an average of their results but a one off. Their Demon had 10" drums and a power booster. They did say their road surface wasn't ideal, but dang.

https://www.curbsideclassic.com/vintage-reviews/vintage-road-test-1971-dodge-demon-340-road-test-takes-a-real-devil-for-a-spin

So yeah, bias ply's and drums are outdated crap. If you're spending any significant amount of time driving on the street nowadays you should run more modern tires AND brakes. 11 feet is a crap load. Not enough to park a road runner like the article says, but still.
 
IMO,that article is flawed. As area lot of HR articles
The discs in the back did not decrease the stopping distance, the drums were simply not tuned to potential; and we both know why.
Sorta like ET and trapspeed.
For street;
I find no fault in rear drum brakes, having driven most of my life with them; some tuned, most not. I PREFER them on the back over discs, as they are, in my experience, trouble free. Just about every all-disc vehicle I have ever had (including my wife's and my three kids) have had, at one time or another, rear brake troubles. And some of them were a total PITA to service, especially with the parking brake system fubared into them.
But hey, it'd good that you shared.
 
IMO,that article is flawed. As area lot of HR articles
The discs in the back did not decrease the stopping distance, the drums were simply not tuned to potential; and we both know why.
Sorta like ET and trapspeed.
For street;
I find no fault in rear drum brakes, having driven most of my life with them; some tuned, most not. I PREFER them on the back over discs, as they are, in my experience, trouble free. Just about every all-disc vehicle I have ever had (including my wife's and my three kids) have had, at one time or another, rear brake troubles. And some of them were a total PITA to service, especially with the parking brake system fubared into them.
But hey, it'd good that you shared.

Not tuned to potential? The brake system was fully stock to start, so, factory everything except the tires. I know for a fact the factory "not tuned to potential" BBP drums will still lock up that size of rear wheel. The argument I see over and over again is that if you can lock up the wheels that's as much brake force as you need. That's wrong, but that's the argument. That car could without a doubt lock up the wheels with those drums unless there was something seriously wrong with the drums. Not just tuned to their full potential either, there would have needed to be something wrong for them to not be able to lock up those wheels.

And yet, the stopping distance still decreased when they went to disks. There was also no mention of an adjustable prop valve in that article, just how to defeat the metering valve in factory combo valve. So you think the disks were tuned to full potential? I bet they weren't. They said after they "carefully tested in the shop parking lot" that "it was time for some actual hard brake testing." See the problem? They didn't even break in the pads properly. So yeah, I think they sold the disks short too.

I think that article is more useful than you give it credit for. They replicated the average car, a "not tuned to potential" factory drum system replaced by a slapped on and "not tuned to potential" disk system.

Besides, I don't have to go just on their work. The braking on my Duster improved when I went to rear disks too. And when I went to 13" front rotors and new calipers. Despite the fact that the 11.75" front disks and 11x2.5" rear drums were fully capable of locking up the wheels.
 
I just pulled the K-H parts off my 71 Duster and am waiting on a Dr Diff Stage 1 kit to arrive. I dug in and thought I'd just rebuild the calipers but the pistons were stuck (car sat for years) and I saw it turning into a charlie-foxtrot, so I pulled out my wallet.
 
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