Plumbing for power disk brake proportioning valve...need help

[elevenssc]

Anyone out there able to take a photo of the proportioning valve on a car with power disk brakes?  I need a little plumbing help (which ports get supply from the master cylinder, and which ports supply the brakes?)  I'm converting my car to power front disks, and installing a new proportioning valve.  I've also got an adjustable proportioning valve (for future rear disk upgrade).  Does the adjustable proportioning valve get installed now, or when I put the rear disks on?

I can post a photo of the proportioning valve that I have if needed...let me know if it would help.

Thanks,

Tom

[Bullitt-]

From my '73

[Chryco Psycho]

install the adjustable valve now , it iwll be more accurate then the factory one for balancing the brake bias

[elevenssc]

SWEET!!!!!! 

Exactly what I was hoping for!  Thanks a bunch!

I know I've said it before, but it is worth saying again...this place is great, and lots of great folks...Thanks again!!!

[elevenssc]

...one more thing...Im guessing the adjustable proportioning valve gets plumbed in the rear brake line down stream of the factory proportioning valve...correct?

[Chryco Psycho]

correct

[elevenssc]

Ok...I need a little help here...

I just have the line from the rear brake port on the factory proportioning valve to the inlet on the adjustable proportioning valve left to plumb.  I was assuming that the fittings were the "small" ones like the rest of the lines that are plumbed to the factory proportioning valve...but it is not.  It is not even the "large" size that is used on the master cylinder.   

I need a little help here...What do I need to finish the job?  Am I missing a reducer bushing?  If so, what are the thread call outs I need.

I'm confused...

[jims challenger]

I just updated mine, you need to cut off the old fitting and add a 9/16"-18 fitting to the existing line. (or use an adapter if you can find one)

Jim

[elevenssc]

Thanks...I'll give this a try...

It's great to have everyone here as a resource.  No matter what you are doing, someone else has already "been there - dont that" and knows what the job needs.

[elevenssc]

I got things hooked up, and fired up the car for the first time this spring.  The brakes still need a bit of tweaking and I need your help...

1) Does the brake booster get hooked up to manifold vaccum?
2) Why is my brake light on in the dash?  I have the wire hooked to the proportioning valve per the photo above.
3) Is there a general rule of thumb when adjusting the booster rod when connecting to the pedal  (that activates the brake light switch?)

The brakes work fine when I hooked the booster to manifold vaccum, but the brakes dont "let go" when I take my foot off the pedal.  It takes about 5-10 sec before the car rolls freely again.  Why?

After about 2-3 minutes, the idle RPM gets pulled down to under 500.  I'm confused...

[Bullitt-]

1) Does the brake booster get hooked up to manifold vaccum?
yes, OE there is a pipe in the manifold to connect to
2) Why is my brake light on in the dash?  I have the wire hooked to the proportioning valve per the photo above.
after bleeding push the pedal very hard to reset the switch
3) Is there a general rule of thumb when adjusting the booster rod when connecting to the pedal  (that activates the brake light switch?)
I've read that the rod going into the master cylinder can be adjusted, nothing to do with the brake light, but it's the same light that comes on when the emergency brake is depressed so problems there could throw you off.

[ShelbyDogg]

After about 2-3 minutes, the idle RPM gets pulled down to under 500.  I'm confused...

Your booster could be a source of a vacuum leak.

[elevenssc]

Should I be able tp pull vac. on the booster with a hand vac. pump?

I can only get to about 6 in-Hg and no more.  The vac bleeds down to zero too.  Not sure if it is the booster or the connections... 

Would a vac leak in the booster cause the RPM to increase, not decrease???

[ShelbyDogg]

Vacuum leak would make the rpm Increase. I never tried a vacuum guage on my booster. Why don't you try replacing it from AutoZone. If it does the same thing, return it for a refund.

[elevenssc]

I'll ask the folks I bought the kit from about the booster vac.  I have to call them about some other stuff.  I'll let you know what I find out...