Drums to discs

Moderator: Moderators

User avatar
Dave-R
Posts: 24752
Joined: Sun Apr 18, 04 11:23 pm
Location: Dave Robson lives in Geordieland
Contact:

Post by Dave-R »

jerry wrote:Dave can I do away with the metering block and run straight out of the master cylinder to the rear and out of the cylinder to a tee then off to front discs
No. Just splice in an adjustable valve as shown in the Mopar Action article on the link posted earlier. Otherwise the rears will lock up before the fronts. So you have to reduce the pressure going to the rears with the proportioning valve.

It helps if you have only 10" drums on the rear. But if you have 11" drums you will need to adjust quite a lot out of them.
User avatar
autofetish
Posts: 5599
Joined: Sat May 21, 11 6:43 am

Post by autofetish »

Below is the only part that seams to be about masters and bosters.

My question is there a diffrence between and master cylender for a booster system or a manual system ? Or it the same master and you somtime have problems with a 4 / 2 bolts set up ??????



Taken from blues post
you'll need, (only) if you now have drums, a master cylinder from virtually any '70-up disc car, even one from such common junkyard dogs as a 1976-78 F-body (Volaré/Aspen.) Later cars ('79-up) used a neat, lightweight aluminum master cylinder, but it was attached to the firewall (or vacuum booster) via only two bolts, as opposed to the earlier 4-bolt arrangement, requiring an adapter plate (Mopar Performance P5249305 or AR Engineering MC1002) to install. Alternately, you may be able to adapt a later 2-stud booster.
User avatar
Dave-R
Posts: 24752
Joined: Sun Apr 18, 04 11:23 pm
Location: Dave Robson lives in Geordieland
Contact:

Post by Dave-R »

autofetish wrote:My question is there a diffrence between and master cylender for a booster system or a manual system ? Or it the same master and you somtime have problems with a 4 / 2 bolts set up ??????.
Same master cylinder if it is power or manual.

Different master cylinder if it is disc or drum.

The "classic" muscle car type is 4-bolt.

From the late 70s-on they are a 2-bolt, lightweight aluminium, with a plastic reservoir. These can be bought new and come in different sized bores to give you a longer travel/easier to apply brake or a shorter travel/firmer brake feel.

Manual master cylinders mount lower on the bulkhead and are connected directly to the brake pedal.

Power brake master cylinders are mounted higher on the bulkhead and have a more complex linkage to the brake pedal.

I hope that covers everything?
User avatar
Mick70RR
Posts: 1885
Joined: Sat Apr 02, 05 8:57 pm
Location: Birmingham

Post by Mick70RR »

The master cylinder for power disc brakes has a 1 1/8" bore. That's what you get in the SSBC kit for power or manual brakes. It's too big for manual brakes, can't get enough pressure on the pedal. I swapped it for a 15/16" bore master cylinder that was listed for an early 70's A body and it made a big difference.
1970 Road Runner, 505CI, 4 speed, GV overdrive, 3.91 gears.
11.98 @ 117mph on street tyres
User avatar
autofetish
Posts: 5599
Joined: Sat May 21, 11 6:43 am

Post by autofetish »

Perfect thanks Guys :thumbright:
Post Reply