OK, the PO on my 31' installed the power brake kit and it looks like who plumbed it wrong! The front outlet goes to the front, rear out let to the rear which is reverse from the original design for the M/C. I know the sites all say to run them in the same orientation as the OE would have been, but why? The master cyclinder has the same size bowls, front and rear. I am changing it around but why does it matter. I have 4 wheel disc, residual valves, etc.. My line of thought says the M/C doesn't know it's backwards and the system is basically the same. (Front and rear discs)
It really doesn't matter if the m/c does not have checks and both bowls are the same size. Disk/drum masters A may have a check in the drum side and B the large bowl is because as disk pads wear they do not retract like wheel cylinders on drums do. So you need a larger capacity on the one side to take care of the caliper piston continualy moving out towards the rotor. The only real exception on the m/c is the ones with quick take up for the low drag calipers,those must be plumbed the OE way.
Many drum/drum and disc/disc master cylinders do NOT operate as 50/50, even if the chambers look to be the same, because the front cylinders are always larger, even if slightly, and certain DOT tests require the piston strokes (volumn) to match the cylinders (volumn) on that circuit. It's not critical on a custom non-production system, as they are close enough for our purposes, but if you know for sure the stock OE F/R plumbing of the master you are using, why not plumb it that way? No good reason not to. Masters with an obvious chamber size difference should ALWAYS run the larger chamber to the fronts on a front/rear system.
Check out the web site for Master Power Brakes. They have a lot of diagrams and info for brake systems. You may need additional residual check valves etc. depending where your master cylinder is located. Also, the bore size of your m.c. is important depending on if you have power or not. Good luck.
Do the brakes work? Find an unpaved alley and lock them up. Do all 4 slide? Are the 4 trenches it make similar?
Brakes work somewhat. I was playing with the car today and they will kind of stop the car, but the fronts seem to be draging pretty bad. I believe the rod between the master cylinder/ booster is too long and keeping pressure in the system. I'll have to open it up tomorrow and check it out some more. Do I need to bleed the system with the car running because of the booster or do they bleed the same as manual brakes?
get somewhere safe and lock them up- if the front's lock first, just run it. if the rears lock first, then the car WILL loop, as the fronts continue to grip while the rear just slides.
Thanks for the input. I re routed the brake lines, re adjusted the rod between the M/C and booster, and re-bled everything. Brakes work great now and I am slowly playing with the adj. valve. The car stops great. I have not locked them up yet, it stops really QUICK and i don't have a seat belt to keep me in the car! LOL
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