L
lalonde441
Guest
someone want to explain to me a bit about this system and why it is so much better that the stock system? thank you.
L
lalonde441
Guest
please explain...why is the system better? more reliable? better stopping power??
TR Custom Parts
Mark Hueffman - Owner
- Joined
- May 25, 2001
Very reliable whereas the Powermaster system has a high failure rate. Convert to vacuum and it is one less thing to worry about. Keep the Powermaster in storage if you ever want to go back to stock.
Why is it better? It doesn't WORK better, assuming that the Powermaster works. In fact the Powermaster, if it works, is probably better overall. If it works. The advantages of vacuum brakes are simplicity, reliability, and price. The Powermaster has an electric motor that runs a pump to compress the gas in the accumulator, which is what gives you power brakes. It has a pressure-sensing switch that makes the motor and pump run when the pressure in the accumulator drops to a certain point. This is a complicated system and is prone to failure.
1. The electric motor can, and does, fail. Vacuum brakes don't have one.
2. The pump can fail. Vacuum brakes don't have one.
3. The pressure-sensing switch can fail, causing the motor and pump to run until they also fail or the fuse just pops. Vacuum brakes don't have this switch either.
4. The accumulator can leak, which drops pressure, which causes the motor and pump to run until they fail or pop the fuse. No accumulator on vacuum brakes.
5. Oh yeah, and the master cylinder (usually seals on the piston inside the cylinder) can fail--and this can happen with either kind, Powermaster or vacuum.
FIVE POSSIBLE POINTS OF FAILURE. Four of which are pretty common with Powermasters (1-4).
1. The booster (vacuum storage device) on vacuum brakes can fail (although I've never had it happen in over 30 years of car ownership).
2. The check valve on the booster (keeps vacuum from leaking out of the booster) can fail. This is more common than a booster failing. Keep a check valve in your car. About $2.
3. The master cylinder, as above, can fail. A flaw all brake systems have.
THREE POINTS OF FAILURE. And they are relatively rare and relatively cheap to fix...
Keith
1. The electric motor can, and does, fail. Vacuum brakes don't have one.
2. The pump can fail. Vacuum brakes don't have one.
3. The pressure-sensing switch can fail, causing the motor and pump to run until they also fail or the fuse just pops. Vacuum brakes don't have this switch either.
4. The accumulator can leak, which drops pressure, which causes the motor and pump to run until they fail or pop the fuse. No accumulator on vacuum brakes.
5. Oh yeah, and the master cylinder (usually seals on the piston inside the cylinder) can fail--and this can happen with either kind, Powermaster or vacuum.
FIVE POSSIBLE POINTS OF FAILURE. Four of which are pretty common with Powermasters (1-4).
1. The booster (vacuum storage device) on vacuum brakes can fail (although I've never had it happen in over 30 years of car ownership).
2. The check valve on the booster (keeps vacuum from leaking out of the booster) can fail. This is more common than a booster failing. Keep a check valve in your car. About $2.
3. The master cylinder, as above, can fail. A flaw all brake systems have.
THREE POINTS OF FAILURE. And they are relatively rare and relatively cheap to fix...
Keith
L
lalonde441
Guest
sounds like a very reliable system for sure! Im sold on the system....now i just have to convert over. Looking into one here on the board. Thxs for the VERY informative feedback!
My general observations from other g bodies I have owned that had vacuum brakes and my 87 GN that I converted was that the vacuum brakes seem to give more assist and more pedal feel.
I am not sorry I converted. I got rid of my Powermaster as I will NEVER waste my money on one of those again. They are a perpetual waste. I cant tell you how many times the stupid brake warning light would come on followed by the rock hard pedal. Try stopping from 70mph or faster after one of these incidents. It was an accident waiting to happen. I bought a used vacuum booster with the pedal from a salvage yard over 2 years ago and it still works great. Its even better now with the b body brakes
I am not sorry I converted. I got rid of my Powermaster as I will NEVER waste my money on one of those again. They are a perpetual waste. I cant tell you how many times the stupid brake warning light would come on followed by the rock hard pedal. Try stopping from 70mph or faster after one of these incidents. It was an accident waiting to happen. I bought a used vacuum booster with the pedal from a salvage yard over 2 years ago and it still works great. Its even better now with the b body brakes
- Joined
- May 26, 2001
Sorry Keith, have to disagree with you here based upon the MANY vac conversions I have done. The vac system works MUCH better than a PM in braking for our cars. The master cylinders are different as you know, and the vac one puts out more pressure/braking force to the rear wheels.
The skid marks on the street in front of my place verified this. A PM will barely lock up the fronts and not the rears. After conversion, same car leaves 4 equal patches of rubber!
No one has ever come back after a conversion and said their car did not stop as well, always the reverse. Now they feel confident with their performance car on the street with a much better and reliable brake system.
