Prop./ Brake valve

[493dart]

Ok guys, i need to know what you did as far as your proportional valve after the disc conversion.  My car is a 70 dart and i put 73' discs up front.

I have what is believed to be a 73-76 A body prop valve.  when i place it up on the frame,  none of the lines match up , as far as size and  rear/ front ports .   It really looks like i have to make all new brake lines  . 

Is this what you guys had to do---or   how did you route everything  ?

[Jim_Lusk]

I've always used the 73-76 a-body piece. You may have an F-body prop valve. Can you post a pic?

[493dart]

here it is:

[attachment deleted by admin]

[Jim_Lusk]

Definitely NOT an a-body piece.

[493dart]

figures--i was told it was and bought it online .

anyone have one on here ?

[Jim_Lusk]

I don't have a spare one, but might be able to get a pic of one so you know what you're looking for.

[ski]

Here's one.

[attachment deleted by admin]

[493dart]

thanks - can u list what each letter corresponds to ?

[ski]

Sorry,

A= master cylinder marked F for front, be careful it's actually the rear reservoir. 
B= right front brake
C= left front brake
D= rear brakes.  They'll split downstream
E= Master cylinder marked R, again be careful this is the front or usually smaller reservoir.

B & C probably can be either way but A & E have to be correct.  You want the larger reservoir to apply the front brakes.

Thanks to Ryan from N.H. for applying the letters to the picture. 

[493dart]

thanks !

[larry408]

I have a extra a-body proportional valve but it is packed for the move that we are making this weekend. If you do not find one and are interested in the one that I have just let me know and I will look for it next week.

[440WIP]

This is handy information.
Is it possible to put this thread (of the picture and the description) up into the tech pages?

[Sixpak]

I took this one out of a 75 Dart with factory discs....

[attachment deleted by admin]

[493dart]

hmmmm......that one looks just like the one i already have. 

[ski]

The one I posted came out of a 73 Valiant with factory disc brakes.


... it was the newer single piston type not the earlier K/H.

[DartKnight]

Weird...the bottom one looks like a B or E-body valve; The one I pulled for my brake swap came from a 74 Swinger with single-piston calipers and looks like the one ski posted. The other ones look like the valve I pulled out of my 74 Charger...I'm a little confused, also.  If it is a dual-piston/single-piston difference, would either one work?

[493dart]

confused here too !

my car has 73' single pistons

[Ed]

All my pre-73 cars have the brass square prop valve.  Ma mopar switched over to the cast iron valves sometime in the early 1970's except in trucks. 

[ski]

I'll see if I can dig out a 72 and earlier that went with the 4 piston K/H type.  If I remember right they look similar to the one I posted but not exactly.  It may take me a couple days to locate one.  Hey 496dart I would just get a 35 dollar adjustable one and plumb it into your rear brakes.

[493dart]

i  might do that--who has them for $35?

i got another one on the way  to try first

[Lars]

Summit Racing has them. Use the old drum valve and plumb the adjustable one into the line that feeds the rear brakes.

[ski]

i  might do that--who has them for $35?

i got another one on the way  to try first

Take a look at the last one labeled 65-72 MOPAR.  Kind of looks like the one you have.

http://www.piratejack.net/proportioning_valves.html

[Sixpak]

I believe the factory started doing a slow transition from brass prop valves to the cast iron ones around the early 70's. Earliest example I can recall of seeing a cast iron valve is in a 71-72 C b body, then I think the E bodies got them in 72 or 73, probably the B bodies around then. I've seen brass valves in A bodies through 74 but after that in 75 most if not all had the cast iron valves. It's just a matter of the factory using up whatever they had in stock and then switching over to something else.

[493dart]

Thats gotta be the one i already have Ski

[moparrr07]

it shows in my 75 chrysler chassis manual that every line had a cast one

[Jim_Lusk]

I just pulled two of the brass ones out of a yard today, along with the spindles. I didn't check the year of the cars, though.

[wedgie]

I know that the combination valve proportions front to rear, and turns on the brake malfunction light, but does it also contain the residual valve?

[67 dartgts]

  Let me see if I understand and can confuse everything even more  The photo that Ski posted iss of the Safety Switch its function is to split the front wheel lines and warn of a system failure frot or rear.  The faiilure would be a break in the system that allows the fluid to drain to the point where the spring pressure inside the switch makes contact turning on the light .  To tell you you have lost fluid..the other system will of course work because it is complety seperate from the other.  If you took the safety switch out of the system.  The rear section of the Master plumbs direct and splits at the rear end.  The front section you can split with a tee to do the right and left.  There is no connection to the front and rear inside the switch.  The proporating valve merly allows you to adjust pressyure to the rear so all wheels brake equally..that is in a panic stop you lock front and rear wheels equally.

  Maynard

[attachment deleted by admin]

[Cudadust]

This is getting a little confusing, those early renditions were distribution valves with a position forow fluid pressure.  The later model combination valves provided some proportioning but this was negated with different tire\wheel combinations. The stand alone proportioning valve is installed in the rear brake circuit and adjusts the amount pressuse to the rears as a safety feature to prevent the rears from locking up first and causing the rear end to come around. www.moparaction.com is the definitive source for brake conversions on Mopar iron and should be consulted for more information.

[ski]

http://www.piratejack.net/troubleshooting/valveFAQ.htm

[67 dartgts]

Per 1967 Dodge/Dart/Charger/Cornet manual
Make your own coclusion.

 Maynard

[attachment deleted by admin]

[ski]

That looks like an all drum brake warning indicator block from 67 and up when all auto manufacturers had to go to a two reservoir systems by federal law. (MOPAR was cheap and had to be forced) The light comes on after you already feel the brake fail. That's not a pre 73 proportioning valve.  Look at the pic I posted and see that the brass block is shaped completely different.  I don't think there is many differences in the moving parts of the two I think it's more of a difference in the sizes of the oriffices depending on which route the fluid takes.  Of course I could be AFU.

[Jim_Lusk]

67s had a separate prop valve behind the distribution block.

[67 dartgts]

Jim's right on here...my 67 GTS has it behind the block in line about under front area on frame rail..

Ski: Yes it a 67 piece but it is the same as on my GTS with front disc and rear drums.  What we have shown here is there is a variety of Valves, Blocks ,Lines and so on on these early models at least.  Nice exchange of info Ski!!

Best advice I can give is if your converting strip donor car of every brake part there is.  Then you at least have all in hand if you are in doubt on something.  If you''r buying a kit get it complete with every thing the manufactuer has for your model.

Brakes the very worst place to try to save money.

Maynard

[NOST440980]

piratejack what a great site. helped me out. thanks, who ever found that one.

[EricMU]

 If you switch from Kelsey Hayes discs to later single piston with the small rotor, can you just re-use the same prop valve that is in the car?

[DartKnight]

If you switch from Kelsey Hayes discs to later single piston with the small rotor, can you just re-use the same prop valve that is in the car?

That's my question as well.

[Sixpak]

YES - re-use the KH disc prop valve for the single piston disc swap - it's the same - the brass one...

[dmn71]

Jumping in here a late but when I did my disk brake conversion this past winter I got a mopar proportioning valve from Right Stuff Detailing for my Demon.  Did not want to put a seperate valve in the line.  Cost was $75

Steve

[Bogie]

Just to throw out another option im using the PROP-BLOCK from SSBC
its $129.99 in Black but its a Adjustable Proportioning Valve and Distribution Block All-In-One  + a brake light switch

[1DART440]

That new block is nice!
I just put a tee on the fronts, bought a $39.00 adjustable valve for the back and tossed the old stock block. Seems to work just fine. Just lacking the brake warning switch.

[SIKPUP]

That new block is nice!
I just put a tee on the fronts, bought a $39.00 adjustable valve for the back and tossed the old stock block. Seems to work just fine. Just lacking the brake warning switch.

 After checking how the stock one worked, it got tossed !   That's how mines done.

                                                                   SIKPUP

[Aax]

496dart...the picture you posted is a valve from a 75/76 A-body w/discs. I have two just like it that I personally removed from the original vehicles (1 from a '76 Valiant w/man discs & 1 from '76 Dart w/manual discs).

I've seen the square brass units mainly in 73/74 disc cars.

I think you're good to go.

[68dodge]

That new block is nice!
I just put a tee on the fronts, bought a $39.00 adjustable valve for the back and tossed the old stock block. Seems to work just fine. Just lacking the brake warning switch.

 After checking how the stock one worked, it got tossed !   That's how mines done.

                                                                   SIKPUP

So you took the block out and are running with a "T" from the master to the front and a adjustable prop. on the rear? What master cylinder are you using? Manual Brakes? I want to run disc brakes all around.

[Small Block]

Bogie: That same unit is in the new Mopar Muscle Mag and it looks lik ethe way to go.

[MarkS]

Finally... something I can contribute to!

I'm a hydraulics instructor at Rosedale Technical Institute here in Pittsburgh, PA and I teach combination/proportioning valves as part of my curriculum.  I'd be MORE THAN HAPPY to share what I know about combination and proportioning valves with anyone that cares to know.  They are a VERY complicated looking device that is SIMPLE to explain.

Shoot me an email at masimoneau1@yahoo.com and I'll get back to you!

[DartKnight]

That new block is nice!
I just put a tee on the fronts, bought a $39.00 adjustable valve for the back and tossed the old stock block. Seems to work just fine. Just lacking the brake warning switch.

 After checking how the stock one worked, it got tossed !   That's how mines done.

                                                                   SIKPUP

I'm liking this idea more and more; the warning light is almost useless, anyway. If you wanted to get picky, I guess you can always add a gauge. I'm assuming that this setup works fine using stock size wheel cylinders out back?

[493dart]

The Brass block looking prop valve  seems to be working on my 70 dart . I have 73 discs on the front .

[moparrr07]

i am running everything stock for brakes inside of the frame and the rear drums, fronts are 11 3/4

it works great with stock 4 drum prop block but when i put on my 11x2.5 finned drums out back im going to t the front and i got an adjustable valve for the back

[493dart]

1Dart440 -----


where can i get the Tee  to tie the front lines together ? What size do i need? Im going with the summit prop valve . Im tired of fighting my NEW brake system !    o[     o[     

[416duster]

My 70 Duster was factory non power disks up front & when I rebuilt the brakes on it the local part store swore up & down that they didn't come with non power disk's only power. I think the master they gave me was for a drum set up. I've since switched that out for a late model truck aluminum one that I know is a disk master. I swapped out the small bolt pattern disks for 73 single caliper units while retaining the factory brass block. Ever since the brakes were redone with the small pattern & with the big pattern the front wheels will only spin about 1 turn when the front end is in the air. I've checked the wheel bearing several times & they are OK, The only thing I can think is the brass block has takin a dump. Any ideas?

[gregpurcell]

I NEED one of the early 68-72 A body  K/H disc brake brass proportioning valves if anybody has a spare. I have the drum brake brass valve which is different.
Thanks in advance!
gregpurcell@gregpurcell.com

[mopowers]

Why don't you just T the fronts and plumb an adjustable Prop. valve to the rears?

[urchinhead]

I just completed a swap to '70 Duster K/H discs on my 64 Dart, and used a Wilwood proportioning valve for the rear, and blocked the original T so that my new master cylinder would feed from the small bowl to the rear drums, and the larger bowl to the front disks. But after all that work, my brakes aren't so great. I'm hoping maybe re-bench bleeding the master cylinder will purge the rest of the air out, but I'm also thinking of switching to the appropriate combination valve or converting to rear disks, and using a custom p. valve. It seems that air must be in the lines, as I have to pump the brakes for them to really work, but I've bled the calipers and wheel cylinders over and over again. I put the adjustable proportioning valve down low, next to the original combo/T on the frame next to the wheel well. Could this be the culprit? I'm at a loss.

[Chatt69chgr]

The cast iron unit was what Chrysler changed over to in early 70's.  Used the brass one before that.  It looks similar to the old brass distribution block that was used starting in 67 when dual master cylinders were mandated and contains the switch that operates the brake light on the dash.  The best way to solve the problem is to keep the old distribution block/switch and plumb in the adjustable proportioning valve in the line going to the rear.  Reason being, this way, you can set the proportion of the brake pressure to the rear to fit your car.  It differs by weight of car, friction lining, condition of discs/drums surfaces, etc.  The old proportioning valve was always a compromise.  They used the same valve in about everything.  Probably wasn't set correctly for any of the cars (and the old units with their rubber gaskets are 35 or so years old so I wouldn't want to trust an old one).  Also, master cylinder is different from drum and disc.  There is a valve in the lines which I think can be removed on the drum unit.  Old wheel cylinders required a hold off valve which are not required now since all replacement wheel cylinders have expanders.

Since brake systems are so important I would ask anyone and everyone to chime in and correct anything that I have got wrong.

[urchinhead]

I was thinking of using a reproduction brass combination valve for '65 - '73 Mustangs that NPD ( National Parts Depot ) sells. With my Kelsey Hayes Discs in the front and drums in the back, I essentially have the same setup as the 65 Mustang.  I'm going to make one last attempt to bleed everything ( again ) before I get rid of the T block ( front ) and Wilwood proportioning valve ( rear ).

[b569rr]

Why don't you just T the fronts and plumb an adjustable Prop. valve to the rears?

This is the route I took. I've used this piece a couple times. good piece.

http://www.stainlesssteelbrakes.com/products/detail/5505/?make=Street%20Rod%20Accessories&model=Prop+Block%3A+Adjustable+Proportioning+Valve+and+Distribution+Block+All-In-One&year=

Tom

[guzzimike]

I got one of these:
 


on my '68 Dart retrofitted with a '73 Duster front disk brake setup (Not power brakes).

FWIW, I was told it was a NOS unit as found on Mustangs. Cost was $45.00.

Works great.

[qkcuda]

Mike, where did you find that combination valve?  The same one on the Pirate Jacks site was $ 57.00.

[qkcuda]

I believe I have finally determined that the brass one Mike posted the picture of, and the cast iron Chrysler one are actually both combination valves (proportioning and metering valve combined), which is what I need.  I am wondering if anyone has a factory service manual from around 75, which shows the plumbing connections for the cast iron valve.  Pirate Jack's sells both valves, and I am going to go with the one that will be the easiest fit for my existing lines and wiring.
By the way, a big    goes to Mark S for taking the time to explain this stuff to me.

[mrhotrod]

Try this site they can set you up with all your brake needs and parts

http://www.hotrodsusa.com/

Residual Valves: Residual valves are pressure valve use to retain pressure in the lines.  The most common use is on a hotrod when there is a floor mounted brake pedal and master cylinder.  Mounting the master cylinder (M/C) below the floor positions it below the calipers.  Gravity will cause the fluid to flow away from the calipers.  The residual valve will retain pressure within the lines.  (i.e. 2 pounds residual valve will retain 2 pounds of pressure, 10 pound will retain 10 pounds.)  Drum brake master cylinders have residual valve(s) built into the master cylinder.  This is needed to maintain pressure against the cup seals in the wheel cylinders.  If you are using a disc brake master cylinder or after market you will need to install a 10 pound residual valve for the drum brakes.  Do not install a residual valve if your master cylinder already has one in it.  This will cause the brakes to lock up after the second application to the brake pedal. 

Distribution Blocks or Combination Valves:  One of the biggest misconceptions is the distribution block or combination valve.  Almost every factory car has one.  This usually serves as a metering block to adjust the proportioning to the rear brakes, as a "T" fitting for your front left and right front brake lines and brake light warning switch.  What people fail to understand is that each car is "engineering" for a specific distribution block based on weight, braking characteristics and tires.  So generally most factory cars have different blocks.

Save yourself some headaches install a adjustable proportional valve in the rear brake lines.

[jacks62440]

My car is not running yet so I can't say it works,  I have a 62 Savoy with 76-79 B- body 11 3/4" brake set up.  2 bolt Alum. MC.  I bought from Rick Ehrenberg. Adjustable brake rod from MP. A nice shiny alum distribution block off a Jeep Cherokee that had disks on the front and drums at the back from the wreckers. I am basically using the alum. distribution block just for connections. I have a MP adjustable proportioning valve ready to go into my rear brake line mounted on the frame with the knob sticking through the floor by my seat. That is mainly for ease of adjustment and so No one can mess with it.  Like I said the car is not on the road yet, but I think the System is Sound.   Jack

[b569rr]

This is a combination distribution block and proportioning valve from Stainless Steel Brake Company. it will set you back about $130. Placing it under the car per someone's suggestion frees up space near the headers.

Tom

[CrazyD]

what's the part number stamped into the factory brass version of the valve?

[Rick_Ehrenberg]

I strongly advise against using that old cast iron stuff. Just leave the stock brass safety switch tee unmolested, and install an adjustable valve anywhere in the rear line. Adjust it on a damp road so that the fronts lock just before the rears.

The metering valve is kind of useless for most of us. It's also called a "standoff" valve, the purpose was to hold off applying the front  brakes until the rear shoes had overcome the return spring pressure, to prevent low-speed front wheel lockup on glare ice!

Rick Ehrenberg

[Rick_Ehrenberg]

Residual Valves: Residual valves are pressure valve use to retain pressure in the lines.  The most common use is on a hotrod when there is a floor mounted brake pedal and master cylinder.  Mounting the master cylinder (M/C) below the floor positions it below the calipers.  Gravity will cause the fluid to flow away from the calipers.  The residual valve will retain pressure within the lines.  (i.e. 2 pounds residual valve will retain 2 pounds of pressure, 10 pound will retain 10 pounds.)  Drum brake master cylinders have residual valve(s) built into the master cylinder.  This is needed to maintain pressure against the cup seals in the wheel cylinders.

Virtually any Mopar wheel cyl mfg, after 1975 uses either high duromoter plasticized piston cups, or "expanders", so RP valves are redundant. Every Mopar M/cyl mfg. after '75 DID NOT have RP valves.

Of course, if, as MrHotrod says, you have a 'rod where the m/cyl is lower than the calipers or wheel cylinders.... ;->

Rick Ehrenberg

[jwmotors]

Why can't you run your rear line straight from the master cylinder port to the back where you split it to the wheels and run the front to the line lock and use that for your tee ?

[Broglock]

Just got done referring to a '77 service manual and they are still showing both the brass and cast combination valves (warning switch/ hold off or stand off / proportioning valve) for both the Volare and Aspen models  this year. Both pictures look very similar the blocks pictured here.
I had one question here are proportioning and hold off valves needed when you are running the same type brakes front and  rear. ie either both drum or both disc.
I had just figured to go after market with the valve since many brake vendors now offer them.

[moparrr07]

Why can't you run your rear line straight from the master cylinder port to the back where you split it to the wheels and run the front to the line lock and use that for your tee ?

because if you do that with no prop valve, the second you go to hit the brakes, the backs will lock up, a prop valve reduces the pressure to the back line, most guy do what you said but they add an adjustable valve in the rear line

[jwmotors]

The drum brake dist. block was not a proportioning valve, it is a t on one end and just a single line on the other end built into a brass block that also held the safety switch that would activate the brake warning lamp on the dash and on a drum brake car you do not need one and your wheels won,t lock up as far as disc brakes I don,t know how the brakes would respond without one .

[oj]

Here's one.

I need one of the brass prop valves like ski posted a photo of in the worst way. Does anyone have a lead on one of these? I can't find one anywhere! 
Bob

[69 GTS Clonvertible]

Ok, anybody plumb in the rear adjustible prop-valve after the brass distribution block but under the drivers door? I really don't want to have to lift my car to adjust the prop valve if I stick it directly after the brass distribution block. So I was thinking of cutting the line and adding the adjuster there. I would need to use a double flaring tool to flare the cut ends correct?
Can somebody knowledgable get me a quick answer as this is all I have to do to pretty much finish.

[jwmotors]

More fuel for the fire , if you are building a drag car or a car with big fat rear tires you would put the valve on the front brakes so you can adjust more pressure to the rears . The valve does not increase pressure it allows you to adjust the ratio by decreasing the line pressure to the brakes it controls .

[moparrr07]

right but even so 70% of braking is done by the front so if you have skinners and slicks, it would about even out with no prop valve

so with a normal front tire and larger rears then you would want to decrease the rear pressure,

its not like you will be locking up the fronts first if you have a decent rear brake setup

[75Dart440]

Ok, anybody plumb in the rear adjustible prop-valve after the brass distribution block but under the drivers door? I really don't want to have to lift my car to adjust the prop valve if I stick it directly after the brass distribution block. So I was thinking of cutting the line and adding the adjuster there. I would need to use a double flaring tool to flare the cut ends correct?
Can somebody knowledgable get me a quick answer as this is all I have to do to pretty much finish.

I built a mounting tab on the subframe connecter and mounted my WilWood prop valve about 8 inches behind the trans crossmember.  I can almost lean out the car door and reach underneath the car to adjust it!!

[69 GTS Clonvertible]

Ok, anybody plumb in the rear adjustible prop-valve after the brass distribution block but under the drivers door? I really don't want to have to lift my car to adjust the prop valve if I stick it directly after the brass distribution block. So I was thinking of cutting the line and adding the adjuster there. I would need to use a double flaring tool to flare the cut ends correct?
Can somebody knowledgable get me a quick answer as this is all I have to do to pretty much finish.

I built a mounting tab on the subframe connecter and mounted my WilWood prop valve about 8 inches behind the trans crossmember. I can almost lean out the car door and reach underneath the car to adjust it!!

That's what I'm going to do unless I plumb it to come up between the door sill and the drivers seat so I can adjust it without having to stop and open the drivers door.

[Stroked68Dart]

One more question for you guys:

I have a stock 68 dart with 4 wheel drums. 

I have installed Willwood front and rear disk brakes (13 inch up front and 12 inch in back).

I still have the stock manual master cylinder for the 4 wheel drums and the stock brass distribution/warning light block and all the stock lines.  All the stock parts are like new as this is a very, very low mileage car that I have now put a 402 cubic inch motor in.

My question is this:

1.  If I take out the residual valves from the master cylinder can I use that with my new disk brakes?

2.  Can I still use the stock distribution/warning light block as long as I put an adjustable proportioning valve between the brass distribution block and the rear disk brakes?

As always your guys help is greatly appreciated and needed.

You can see pictures of some of the work I have done on this car at www.billchatfield.com

 

[moparrr07]

ill answer # 2

you can leave it in their, but you put on some high buck brake kit, i would just pull it out, t the front and plumb the rear to the adj prop valve, i would pull it off and make it look nice, why leave factory parts in their if they are unneeded with 4w disk?

[jwmotors]

http://www.strangeengineering.net/catalog/index.html

Here,s some info some might find useful on the great prop. valve debate

[oj]

 I have found a porp valve from a Jeep Grand Cherokee that is almost identical to the 73-76 a body piece. But I think it is for 4 wheel disks. Can I use the Jeep piece with an adjustable valve in the rear drum brake line on my Duster, which has disks on the front? Eventually I will install 4 wheel disks on the Duster but that will be quite some time. If the Jeep piece will work for now it would save some trouble latter.
Thanks

[moparrr07]

if you put in the jeep one, plus an adjustable one, thats a double prop valve, just put a t on the front lines and an adjustable valve on the rears, no combo valve

[75Dart440]

I left the drum brake valve in (used only as a T for the front and pressure warning light for the dash that way).

Here is a picture of the Wilwood unit i mounted to the sub frame connector under the drivers door.

[69 GTS Clonvertible]

I left the drum brake valve in (used only as a T for the front and pressure warning light for the dash that way).

Here is a picture of the Wilwood unit i mounted to the sub frame connector under the drivers door.

Thats almost how I mounted mine, and the same goes for the stock distribution block I left it in.

[75Dart440]

I think it works well in that location.     I can lean out and reach it without leaving the seat.  Car stops good so far and I haven't yet made any adjustments to it!!  Took the car out on Sunday for a few street striping sessions though!! javascript:void(0);
4 speed

[Winter]

 I now use the normal wheel cyl.15/16",with expander cups. 

Make sure you inspect the inside of the cylinders, the chain store's (Econo, and TruTorque)  brands are switching the no cup expander type 7/8" ,for the 15/16" wheel cylinder in the 10x2.5" drum type rears.

[MoJoe]

That new block is nice!
I just put a tee on the fronts, bought a $39.00 adjustable valve for the back and tossed the old stock block. Seems to work just fine. Just lacking the brake warning switch.

 After checking how the stock one worked, it got tossed !   That's how mines done.

                                                                   SIKPUP

I'm liking this idea more and more; the warning light is almost useless, anyway. If you wanted to get picky, I guess you can always add a gauge. I'm assuming that this setup works fine using stock size wheel cylinders out back?

  I did this and used a line lock then I wired the warning light to activate with the line lock, I did this cause I have a on/off toggle for the line lock under the dash and I couldnt remember wich way was on.

[bigblockkid69]

whats up guys, just opened up my account so im  new to this  site! well id better get to the question!!! i put 70's abody disc up front on my 69' dart and 96' jeep gc rear disc out back, when i pump the brake pedal the fluid sprays out the front brake resevoir on the master cylinder. i didnt change the prop valve or residual valve, so im thinking the residual valve may have went bad. any input would be awesome cuz im kinda stumped 

[75Dart440]

I don't think that the prop (or combination) valve would cause that.  Sounds like a problem at the master cylinder itself.

[south tex mopar]

Sorry,

A= master cylinder marked F for front, be careful it's actually the rear reservoir. 
B= right front brake
C= left front brake
D= rear brakes.  They'll split downstream
E= Master cylinder marked R, again be careful this is the front or usually smaller reservoir.

B & C probably can be either way but A & E have to be correct.  You want the larger reservoir to apply the front brakes.

Thanks to Ryan from N.H. for applying the letters to the picture. 

Hey, by chance do you still have the picture of the prop valve, that applies the letters to the picture. Thanks it will help out alot

[spanky006]

Ok so I am new here and I am hopin you guys can help me. 

I got a 65 Dart that I just completed a front break conversion and I can't seem to get a straight answer for this question;  Do I need to run a Prop Valve or not?

I bought a dual master cylinder and after-market 8 in Bendix double diaphragm power booster to replace the stock single master with no booster.  The tires are the same size all the way around and currently the break set up is disc up front drum in back with no intentions of making it disc all the way around.   

[79ramcharger]

Disc in front drums in back you definitely need a prop valve.

Steve

[spanky006]

Disc in front drums in back you definitely need a prop valve.

Steve

Hey Steve, thanks for responding.  I am curious.  I just can't get a straight answer, some say yes I need one, and some say I don't need to run one.  The car seems to be stoping just fine.  I haven't had a chance to lock up the tires and see which ones lock up first. 

[jcc]

Disc in front drums in back you definitely need a prop valve.

Steve

Hey Steve, thanks for responding.  I am curious.  I just can't get a straight answer, some say yes I need one, and some say I don't need to run one.  The car seems to be stoping just fine.  I haven't had a chance to lock up the tires and see which ones lock up first. 

1. You definitely need to do a lockup test under normal conditions ( but not in traffic of course) first.
2. I just reviewed a recent lengthy HP Brake book, the author numerous times states using the factory valve as best choice, but he never relates that statement as to what mods would negate that choice, like changing to a big block (weight balance), tire size/compound changes, suspendion changes, pad compound changes, etc That suprised me.
3. He was emphatic that two valves in series should never be used.
4.  IMO for a street driven modified brake system car driven slightly aggressively, an adjustable valve controlled from drivers seated position is required, and I see little reason to omit this
5. Design balancing of the system is the most important and first step according to the author, and an adj valve only for fine tuning, and they only control approx 59%.
6. I always thought a balance bar system was ideal, he says no, a valve is better since it is NOT linear in applying pressute, and says that is an advantage, and he backs it with graphs, etc
7. So my answer, install an adj brake valve.