Brake distribution block

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69b7bbgts

69b7bbgts

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Hello everyone hope you're all staying nice and cool in this hot July quick question I have a big block 69 Dart GTS 383 4 speed I'm going to put Mopar 73 and newer disc brakes on it pin Style,10 1/2 drums are in the rear will I have to have a proportioning valve for the rear? Or has anybody just put the brakes on and been okay with it like that ,it is manual brakes
 
My understanding is that stock distribution block will work but need to add a proportioning valve if you don't already have one.
 
many years ago, when I put late model disc brakes under the front of our 1st 67 B'cuda I didn't even change the master cylinder right away. The drum/drum master and distribution block worked. I corrected all that when I upgraded to power brakes, more than a year later. By that time the front pads were about half way gone and that portion of the drum/drum reservoir was empty. Front got a little air in. Wasn't the best way to do it but I did have brakes.
 
Try it. Easy to add later. Do you have disc or drum front brakes now? Going larger or adding front disc and replacing drums? This probably won't help but I had a disc front, drum rear in my 72 B-Body. I installed larger 73 up 11.75 fronts and Jeep Grand Cherokee disc rear to my 8.25. Same power M/C. I did add a prop valve. Not sure of your intended use but you are nose heavy with that BB. Not to mention all that power. Think inertia.
Here's the thing about drum rears. They work great, however they can lock easily in a hard stop they way they transfer energy from one pad to another which can kick your rear end out. Been there. With a proportioning valve you can almost eliminate that.
 
69b7bbgts said:
Hello everyone hope you're all staying nice and cool in this hot July quick question I have a big block 69 Dart GTS 383 4 speed I'm going to put Mopar 73 and newer disc brakes on it pin Style,10 1/2 drums are in the rear will I have to have a proportioning valve for the rear? Or has anybody just put the brakes on and been okay with it like that ,it is manual brakes
Click to expand...

Would have to be either 10 or 11 inch rear drums.:thankyou:
 
A friend & I recently converted his drum brake Duster to front disc. He bought an after market adjustable proportioning valve & we are still doing small adjustments on the valve to get it to brake correctly. We are getting close now, maybe one or two more test runs.
 
69b7bbgts said:
Hello everyone hope you're all staying nice and cool in this hot July quick question I have a big block 69 Dart GTS 383 4 speed I'm going to put Mopar 73 and newer disc brakes on it pin Style,10 1/2 drums are in the rear will I have to have a proportioning valve for the rear? Or has anybody just put the brakes on and been okay with it like that ,it is manual brakes
Click to expand...
If you have bigger tires on the rear than on the front, then you will likely be fine without a P-valve. If not, you can fine tune the rear by swapping wheel cylinders. There are 3 or 4 sizes to chose from. The factory proportioning IMO, was far too conservative. But I guess they had to protect their azzes.
 
There is nothing wrong with being sure a car's braking is effective under all the conditions they will needed.

It's really dangerous to suggest that people who are not knowledgable or experienced redesign a brake system.
There are many factors that go into how a brake system feels and performs.
It only takes one situation where they don't work as they ought...

@69b7bbgts
My suggestion is the first thing to do is go to the Chrysler Master Tech booklets and read up about brake hydraulics, as well as how disks and drums work. Scroll down to 1966 - 70 for the most relevant ones to your car.

Whether you decide to convert to front disks or stick with the drums is up to you. Either way, it might be worth your while to consider Rochester Brake & Clutch when it comes to linings for the shoes (and pads). Its important that the drums on the car, whether on just the rear or on all four, work well and the right combination of linings is a big part of that.
 
69b7bbgts said:
Hello everyone hope you're all staying nice and cool in this hot July quick question I have a big block 69 Dart GTS 383 4 speed I'm going to put Mopar 73 and newer disc brakes on it pin Style,10 1/2 drums are in the rear will I have to have a proportioning valve for the rear? Or has anybody just put the brakes on and been okay with it like that ,it is manual brakes
Click to expand...
How about some punctuation and proof reading?
What is;
10 1/2 drums are in the rear
Click to expand...
So far as I know there is no such thing as 10 1/2 inch drums, nor 10 x2.5 rears.
So far as I know the standard rears are 10x2 drums, and 1.75" linings, with 7/8" wheel cylinders.

AJ/FormS said:
If you have bigger tires on the rear than on the front, then you will likely be fine without a P-valve.
Click to expand...
If you run 4 same sized tires, then I recommend to run the 73 up disc/drum Combination Valve

On the back of my 1968 Barracuda I have those 10 x2s and 1.75s and 15/16 wcs.And I have 295/50-15 BFGs or Cobras, and:
On the front I have 235/60-14 same brand tires running the KH 4-piston calipers. and
I run no rear Proportioning, and
the back end gives me ZERO problems, with phenomenal straight-line stopping. and
threshold braking, I can slow and steer at the same time, and
braking in a corner is NOT exciting in any way.
Ok
I realize that you cannot fit 295s on your Dart. But you can fit 255s, and swap wcs to 7/8" or 13/16" ,and do some testing.
 
First off thanks for all your input. I will work on punctuation, I voice text and get lazy about cleaning it up. First I do use Rochester Clutch and Brake they are in my backyard and they give me great clutches and special brake material on my shoes which are 10 inch by 2 inch rear drum, it has the big Mickey Thompson's on the rear 13 wide bye 31 tall but they are a fairly hard compound so they don't have quite as much traction as you would think. The front tires are the matching Mickey Thompson little Skinny's on 4 inch Cragar Wheels so not a whole lot of braking power in the front I imagine even with disc brakes. From what I understand that block is not a proportioning valve but merely a distribution block correct me if I'm wrong please. And yes I will look at the Master Tech articles I love watching them on YouTube I watch them all the time and always learn something from them.

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This is mock-up stage hope to have it running in less than a month it's a former S/S G car it was campaigned in the late 70s. Original GTS 4 speed 383 car I am still in touch with the original owner they just celebrated their 50th anniversary and I have pictures of them on their wedding day in the car.

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I repainted it in the original B7 blue, when I got it it was B5 with the black vinyl top missing that it came with. Original owner spec'd the car out when he was in Vietnam, so it also has the export tag next to the fender tag. Another member on this site has a almost matching small-block GTS 4 speed B7 car which is 6 days away from mine on the build date.
 
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