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Hello, I am having front brake problems,

I am working on my 68 dodge dart, just seems im not gettting much brake psi to my front disc.

I have rear drums and the grab before the front, so I installed an adj brake p-valve. well i can back off psi to the rear, and the problem seems worse. The Master Cly is and original, and according to the shop manual (motors) the MC has a redisule valves for the rear drum brakes and the front disc. The front should have a  2 lb and the rear a 10 lb, but what i found out is my MC doesnt have any? I also have ecessive pedal travel..which i think this is causing that. Also if i purchace a replacement MC from A-1 cardone their MCs do not have that valve either.. I have bled, replaced and it just doesnt get any better..

do i need the valves?

if it matter the rear still has the original wheel clys.

every thing is new or reman, and if in doubt it was replaced.

is there a test i can do for front and rear brake psi?

is ther a test to find out if i need these valves?

thanks for any help.  

replace or rebuild the master cylinder...
when the pressures drop... its usually the internal seals in the master..

there are several different chambers...   the seals can be ruined when the master is full stroked through a rusty area...




you can get a brake pressure gauge set from several sources..

http://www.summitracing.com/parts/SSB-A1704

http://www.jegs.com/i/Stainless%20Steel%20Brakes/884/A1704/10002/-1?CT=999

as for the reman master... about half the time.. for older cars.. there are brand new imported versions in the box..  i have had one problem with them... the lids don't fit well...  the lid metal is thin and they are usually bent... so when you step on the brakes.. the fluid leaks over the top of the master .. this is not good... not all.. have this problem... just a few..  and you can fix it by straightening the cap .. making sure it fits flush without the gasket..  then install the gasket and try it..

you might invest in a 20 or 25 buck brake bleeder hand pump kit..  so you can pull the fluid through the lines...   with care..

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92474

if you need more information.. post it..


here is the info on the disc reman brake master for a 318 dart  from az..

Master Cylinder (Brake System)
For your 1968 Dodge Dart 5.2L 2BL 8cyl
Part Number: M1487
Weight: 6.3 lbs
Warranty: LLT
Application: With front disc brakes
Bore Size: 1"
Cylinder Honing: Never Honed
New Sleeved Bore: Yes
Primary - Hole Size and Location: 1/2"-20 Fender Side
Secondary - Hole Size and Location: 9/16"-18 Fender Side


you might also find some interesting info on this link...

http://www.moparmusclemagazine.com/techarticles/suspension/mopp_0610_plymouth_gtx_disc_brakes_install/index.html

its from the mopar muscle magazine..  putting disc brakes on a 68 dart...