Joined: Thu Feb 24 2011, 09:02PM
Location: Upstate, NY
Posts: 40
Hello everyone, this maybe a very stupid question but I am unsure of the answer. I am doing a front disc conversion on my 66 fury, parts are from a 73 Chrysler. My question is do I need to run a booster with my new dual master cylinder, or can I just mount the master cylinder to the firewall without one? Thanks in advance for your advise.
Did your car have manual or power brakes before your conversion? This is important because there are two different brake pedals that have their pivot points sevral inches apart. If your car had power brakes, then yes you need a DUAL Diaphragm booster and the proper disc brake master cylinder. The easiest one to find is for a 74-78 Monaco/New Yorker. These are easy to get, unlike the 67-70 booster/master combo, and bolt right in.
If your car had Manual brakes, then all you need is the correct master cylinder (big bowl in the back for the front brakes/small bowl in the front for the rears)
<span class='smallblacktext'>[ Edited Sat Mar 02 2013, 11:28AM ]</span>
Joined: Wed Nov 17 2010, 03:28PM
Location: florida
Posts: 1311
Don't need a booster. If you want a booster,like kraut said,you would need the correct pedal.manual discs work fine and some prefer it of power discs.the biggezt improvement is the dual master over the single pot.I have done the exact same to my 66.
Joined: Fri May 08 2009, 10:41PM
Location: Finger Lakes, NY
Posts: 315
It takes a tremendous amount more force to stop a car with disc brakes than with manual. While disc brakes resist fade as they dissipate heat better etc, drum brakes are self energizing therefore require less pedal effort.
If you are putting disc brakes on, I would recommend adding a booster. My father-in-law has a '53 Studebaker Commander he converted to disc brakes without a booster. It takes quite a bit of two foot effort to shot that car quickly...it is much, much lighter than a C-Body.
Aquaman, remember that the pedal for manual brakes is designed with way higher leverage force, to make up the difference that the booster helps with in power brake systems.
Adding a booster to a MANUAL brake system is asking for 4 wheel lockup every time you apply the brakes.
A properly set up manual disc brake system won't take much more pedal effort than a similarly equipped power brake system. If it's taking too much effort, something is out of whack.
Since you have the manual pedal, you just need to find the right Dual Master cylinder to work with it.
Mopar did make cars with manual disc brakes, the piston in the master cylinder is a bit larger in diameter (about 1/8") than the ones used with power brakes. You're going to have to do some research to find the correct one (I'd start by looking at B/E body masters - better chance of finding one for manual discs)
<span class='smallblacktext'>[ Edited Sun Mar 03 2013, 12:43AM ]</span>
Joined: Thu Feb 24 2011, 09:02PM
Location: Upstate, NY
Posts: 40
I do believe I cave the correct dual mc for the conversion. Can anyone give some advice on the correct proportioning valve I should use with the setup?
The 73' model that goes with your setup would be ideal, but if you can't find one you can always go with a manual valve like I did (about $40 from Summit)
I did a conversion from SSBC it was from manual drum to manual disc the master cylinder they used was from an a-body with manual disc brakes also used the stock valve with an adjustable one added to the rear Joe