[Fletcher]

I am having to put a vacuum pump in my car to help with the power brakes. I have found 3 or 4 on the market ranging from about $200 - $350. The only difference I can find is the size. What I am concerned about is the recovery time and the noise level. And anything else that might be good to know about these units.

Any comment would be greatly appreciated.

[pepi]

I run the one master power brake sells, I went that direction because it has a pressure switch that cuts the pump off when vacuum is achieved, that also applies with your foot holding brake.

My pump is located under the car and I have side pipes that are loud so I only here the pump before I fire the car. I messed with the noise for grins just to see if I could knock it down some.

Here is what I found that little muffler is about as quiet as it gets, tried to run a rubber tube and attach the muffler at the end , no real difference in db level. about the best way I figure to get it down might be to completely enclosed it like you would do to a computer. You could trunk mount it that way.

Something else I tried was a reservoir tank to see if I could cut down the cycle time, and all I learned there was that it made the pump run longer because of the volume increase using a reservoir.

I would be interested to know the pump you end up using, for more knowledge.

Here is a link you may not have thought of RVs use these pumps and I would guess noise is an important feature in that application; http://www.readybrake.com/electricvacuumpump.html

As I said before my car is plenty loud and I do not here the thing once the motor is running.. What's that saying loud pipes hides the vacuum pump noise or was that saves lives ? So there it is all I can think of regarding the use of an electric vacuum pump, if you think of another question let me know...

[Fletcher]

Thanks for the input. I checked out the trailer pump but it only takes me up to 15". Master Power brakes tells me I need 18" for it to work right (I've got an underfloor MPbrakes unit).