Upgrading from kelsey hayes to???

AJ/FormS said
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

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.