Hydroboost Vs Vacuum Vs Powermaster
Those pumps have phenolic vanes, and brake fluid has no lubrication to speak of. When they wear, they can foam the fluid, or the motor works itself to death trying to reach the preset switch pressure setting needed to turn off the motor. The other problem is the seal between the pump side and the 12v side leaks fluid into the motor and shorts it out. It is really hard to find a cure for the pump situation. We use new hydroboost assys, which of course, run off of the p/s pump. If the pump is running, (usually when you are driving) you will have power brakes, and enough power brake pressure (1200-2000 psi) to stop the car at high speed, with the volume and pressure needed for 4 disc brake conversions. Think of this: when you apply the brake to spool up the turbo, the p/s pump is spinning faster, supplying more pressure into the hydroboost. It just locks down harder. Pulling 10lbs or more boost is easy, holding the car solid. There was one guy that was running the stock crank pulley, (designed for cruising in overdrive) that actually was leaving the line at 6000rpm. The problem with that is the p/s pump is turning 10,000rpm. Too much! For drag race, slow the accessory speed down. The hydroboost (contrary to some) cannot fail. They only leak after many miles of dirty fluid or overheated fluid. They do need clean fluid and with that they can last 200,000 miles. The master cyl can be replaced separately, and easily, which gives tuneability for different caliper combinations. A plus is that the p/m and the h/b use the same brake pedal, saving a bunch of labor. Spin off the 4 nuts, reinstall, the master lines are the same, hook up new hoses to the p/s pump, and it works. Check out the picture gallery at POWERBRAKESONLINE.COM