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Adjustable proportioning valve for disc brake swapped 14FF questions.

Square bodies used 3/16" lines for the front brakes, 1/4" to the rears,all the way from the master cylinder back...

Newer trucks I've seen sometimes use 3/16" on all 4 wheels..
 
You can gut the factory combo valve. Look up the 'atron' writeup in here, and that will work fine.
 
So the prop valve from Jegs that I ordered yesterday has no ETA on when they'll receive it... kinda weird cause they told me they would receive their shipment yesterday or today and it would ship to me todat or tomorrow. Glad I called them and glad they hadn't charged me yet.

Went with a Wilwood unit https://m.summitracing.com/parts/wil-260-10922

Both the inlet and the outlet are 3/8-24 IFF. Reading reviews about how people couldn't use 1/4" line in them.

Called Wilwood and they didn't have the adapters, called inline tube and got the adapters for $4ish each.

The adapters are 3/8-24 IFF on the male end and 7/16-24 IFF on the female end.
 
diesel4me said:
Square bodies used 3/16" lines for the front brakes, 1/4" to the rears,all the way from the master cylinder back...

Newer trucks I've seen sometimes use 3/16" on all 4 wheels..
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Did that one bolt up exactly where the old one was on the front x-member?

How are your brakes?
 
handloader90 said:
Did that one bolt up exactly where the old one was on the front x-member?

How are your brakes?
Click to expand...

It did on mine. it's an 80 - had a little interference w/ the ORD steering brace that's in there.

Brakes well - can lock up the 37's. But I also changed out my MC
 
I'm gonna clarify this. I got my rear axle from a later model 2500 - and compared the brake piston areas front and rear on that truck to what I had on my truck now and the jb8 has roughly the same piston area as the late model 2500 that my axle came from. So it was already 'balanced'.
 
Truckman4life said:
I believe that is correct, GM just runs the stupid special size nuts on them to connect to the MC.
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Why GM does that on square bodies,I cant say...the master cylinder has a weird 9/16 x 20 thread port for the front brakes ,so a equally weird fitting for the 3/16" line has to be used--the rear brake port has 1/2" x 20 thread,which also requires an adapter to neck down to 7/16"x 20 threads so an aftermarket brake line fitting will screw into it..

Those adapters can usually be found at parts stores,but might require some digging through drawers of mixed up fittings,best to bring your old fittings to match up--few stores keep their assortment of fittings in the correct compartments in those drawers...

They also sell short lengths of brake lines with the "weird" fittings already flared in place too at some stores..

Only Autozone has sold me some adapters that were in blister packs--which made it impossible to match up--once the package was open--you owned it!..but they were only like $2 each...these fittings are one of the things that stonewall you on a Sunday afternoon often--cant find any till Monday morning,if at all...
I have resorted to cutting the old brake line off close to the oem fittings and use a 6 point socket to remove them,then drill out the remains of the old steel line,and re-use the original fittings..better than walking to work Monday morning..:surepal:..
 
chris85 said:
So this valve says it's not good for a 1/2 ton 4x4, due to weight, but it has C30s in the application list?
I would assume a c30 is pretty close in weight to a 1 ton k5?

Just wondering because i was looking at using this valve for my setup.
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It's basically a gutted combo valve. The weight of the truck doesn't really matter, it's about matching the front and rear pad areas to balance the truck.
 
I'd gladly trade my 14bff w/detroit and disc brakes for a like axle with the old drums on it. The rear disc conversion just isn't that nice on the street and the ebrake is useless.
 
cuervo said:
I'd gladly trade my 14bff w/detroit and disc brakes for a like axle with the old drums on it. The rear disc conversion just isn't that nice on the street and the ebrake is useless.
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There's a reason I used a later van axle for my swap. Removable drums are the cat's meow for my driving patterns.
 
diesel4me said:
the rear brake port has 1/2" x 20 thread,which also requires an adapter to neck down to 7/16"x 20 threads so an aftermarket brake line fitting will screw into it.
Click to expand...

I thought the flare fitting on the 1/4" rear line was 7/16-24?
 
Some master cylinders had 7/16 x 20 threads and others had the 1/2 x 20 threads in their rear ports...rebuilt ones often came with the adapter fittings in the box if the casting had the larger sized port..
 
diesel4me said:
Some master cylinders had 7/16 x 20 threads and others had the 1/2 x 20 threads in their rear ports...rebuilt ones often came with the adapter fittings in the box if the casting had the larger sized port..
Click to expand...

Interesting, I thought the thread pitch was 24 instead of 20.
 
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