Disc brake upgrade questions

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ValiantOne

ValiantOne

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Hey All,

I'm upgrading my brakes to front discs. Car is a 68 Val which had 9 in drums all the way around. The rears have been changed over to 11x2.5, while doing a 8.75 rear end swap.

The fronts are next. I have a 10 in. set up for the fronts including a late K member, late control arms, spindles etc. I also have a late master cylinder with the large resivoir for the disc end.

I do not have a late model stock proportioning valve from a 73-76 car. Do I even need it? Can I use one of those after market adjustable proportioning valves instead with the existing metering block?

If so, can someone recommend one? And where I would install it.

Am I forgetting anything else?

Thanks

CE
 
I WOULD use the aftermarket valve.

You want it in the line to the rear brakes, and you want it between the old distro block/ warning switch and the rear brakes.
 
Has everything you need, including the brake switch, so it can be a stand alone replacement for the original distribution block too

http://www.summitracing.com/parts/wil-260-11179/overview/

wil-260-11179_ml.jpg



Or you could leave the stock hardware in place and just install this one inline

http://www.summitracing.com/parts/wil-260-8419/overview/

wil-260-8419_cp_ml.jpg
 
Very cool. I would like to leave the stock dist block and lines in place as they look darn good.

If I installed that single valve on the subframe connector would it do okay down there? Seems like dirt, water, rain, etc would get to working on the seals pretty good after awhile. Yes, no?

CE
 
ValiantOne said:
Very cool. I would like to leave the stock dist block and lines in place as they look darn good.

If I installed that single valve on the subframe connector would it do okay down there? Seems like dirt, water, rain, etc would get to working on the seals pretty good after awhile. Yes, no?

CE
Click to expand...

I mounted my stand alone valve under the driver seat close to the body lip under the car. Looks great and easy to get to if needed. Also did not have to re-bend any tubing due to it having a bend there already.
 
I would never consider anything smaller than the 11 3/4" police/taxi rotors & calipers for the front. Add a rear Econo disc kit from Dr Diff for a few hundred and you can retain and use your 4 wheel drum brake kit distribution valve and light switch. If you have manual brakes, run a smaller than 1" bore master cylinder.

This combination is extremely well balanced, provides dramatically improved braking, pedal feedback and modulation and is much safer overall. I am running this same set-up on my a-body and my e-body with a big block and power assist. The manual brake are much easier to modulate during high speed, spirited driving on road courses.

In the end, its a little money well spent to stop better.
 
I wouldn't mount the adj prop valve down in the mud, though many do. Mine is right under the MC, as many brake kits do, but I don't have the pressure-imbalance switch in my early cars, so no "down & up" plumbing like you would have to do. I did keep my distribution block, which is just a 4-port "tee", but only the front tubes use it now. If you did use a later "combination valve", it probably won't be direct bolt-up and you might have to rework your tubes to fit, plus there is no adjustment.

I thought about installing an imbalance switch (like post #3), but would also have to add wiring for it. I expect it would give limited utility. When the MC in my 69 Dart failed long ago (pedal went to floor), it never lit the warning bulb. I expect the piston was rusted stuck, as in most cars. But, I didn't know about changing brake fluid regularly then. Today, I use silicone fluid so no more rust. Still, my new MC's have a reservoir level switch which will warn me if one circuit is leaking, which seems sufficient.
 
I just put 76 Dart Disk brakes on my 64 Barracuda, slider calipers, work like a dream car actually stops now! I had 9 inch and they sucked.

Hope that helps.
 
I never had trouble stopping my 69 Dart w/ 9" drums. It could skid the tires, and evenly, so please tell me what more any brakes could do? Most of the "drums didn't work" cases were due to incorrect maintenance. But, I did overheat them once going down a long gravel road in the mountains where I couldn't use the tranny enough to slow. That is where disks excel over drums (faster cooling) and the reason for the federal mandate ~1974.
 
I changed over for the brake fading under heat and traffic. Mine worked ok, had trouble now and again with even stopping. But braking distance disks can't be beat.
 
CE

I just re-read your initial post so if your going with 10 inch drums all the way around the. No you do not put a proportioning valve in, they didn't come like that, there is a valve in the master cylinder.

Now if you put disk brakes on you may with big drums in the back.

On my 65 Signet I have a 8 3/4 rear with 10 inch brakes with disk brakes up front, I did that because of the bigger brakes in the back, used a stock valve from 76 Dodge Dart.

In my 64 Barracuda I put 76 Dart brakes up front and left the small 9 inch brakes in the back, no proportioning valve brakes are small enough.

My point is the reason there is a proportioning valve for the rear is so the rears don't lock up before the fronts. The rears will lock up because there is no weight back there.

Make sense?
 
BillGrissom said:
I wouldn't mount the adj prop valve down in the mud, though many do. Mine is right under the MC, as many brake kits do, but I don't have the pressure-imbalance switch in my early cars, so no "down & up" plumbing like you would have to do. I did keep my distribution block, which is just a 4-port "tee", but only the front tubes use it now. If you did use a later "combination valve", it probably won't be direct bolt-up and you might have to rework your tubes to fit, plus there is no adjustment.

I thought about installing an imbalance switch (like post #3), but would also have to add wiring for it. I expect it would give limited utility. When the MC in my 69 Dart failed long ago (pedal went to floor), it never lit the warning bulb. I expect the piston was rusted stuck, as in most cars. But, I didn't know about changing brake fluid regularly then. Today, I use silicone fluid so no more rust. Still, my new MC's have a reservoir level switch which will warn me if one circuit is leaking, which seems sufficient.
Click to expand...

I was wondering if I could install the " imbalance switch" before the stock distribution block as to keep the switch up in the engine compartment. There it would have a bit more protection and be easier to adjust.

Good, bad?
 
Sure you can, if your "distribution block" is now just a "tee" for the front circuit. Most after-market kits mount the "combination block" right under the MC.
 
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