Posted by Alex J [216.54.94.2] on Monday, April 15, 2013 at 15:48:46 :
In Reply to: did you put that disc brake system posted by clueless [201.198.209.89] on Monday, April 15, 2013 at 15:28:14 :
No, not stock axles. Eaton H072/Ford Dana 60 hybrid front, and an Eaton H072 Rear with a disc brake conversion kit.
The displacement of the pistons ends up affecting your bias, which is why you will still want a proportioning valve unless your dual MC system is set up for each end of the system. Twin piston area is only slightly larger (two small pistons) vs the rear brakes at one larger piston each. Usually the front axle wants more brake force, but pressure breaks down to force over an area.. that area being your piston surfaces relative to the master cylinder. Prop valve helps bias this if the balance is off ie, adjusting your pressure front to rear to compensate for piston area differences. When you are towing, it may change though. The dynamics of each vehicle are different.
Your use of the word power may have me confused though. You depending on your brake setup, you may need more or less force from the master cylinder. My big bore Chevy calipers ('75 K20 Fronts) used on the rear are easy to push, ie lots of fluid, so a long pedal throw but it makes the brakes feel spongy. I have this setup on my trail rig. I like it though because it gives me more of a delicate control of the brakes when descending something difficult. It also means I can use one tip toe to hold my 5k lb jeep standing on its nose.
Anyways, you should measure your piston areas, and calculate the volumes needed and then match your Master cylinders appropriately.