Big cams can wreak havoc in a vehicle with a power brake booster. The bigger the cam, the lower the vacuum number. Inherently, the lower the vacuum number the harder the brake pedal is to press. This doesn’t have to be the case. With our Silent Drive Vacuum Pump, you can remove the engine from the equation and use our stand alone pump to provide the vacuum necessary to properly run a vacuum brake booster. The drawback to a vacuum pump has always been the noise. With the use of our OEM quality rotary style motor, noise is a thing of the past.
People who are helping diagnose certain brake problem conditions - in particular a hard brake pedal - often suggest that you measure the vacuum pressure. The advice will sometimes mention that your engine must produce more than 18” of vacuum to give that nice easy pedal feel. In fact, we just provided that explanation in our recent Tech Talk article on diagnosing causes of a hard brake pedal.
Because we are gear heads, we take every chance to look under the hoods during car shows and swap meets. One of our guys just got back from a big show and he was surprised by how a mistake he saw so many times. To use his words, “How could something like this be wrong on so many vehicles?”
Acommonly heard complaint from people and in particular street rod builders is that they really want to enjoy the benefits of a vacuum booster. So you ask…………“What is the problem?” More often than not, the problem is simply a lack of space. Think about it, you have a street rod with the master cylinder mounted to the frame rail under the car. Right next to the master cylinder is the exhaust system or some other barricade. Or you are building a muscle car with some massive engine in a car where a four-cylinder was tight. There is probably barely enough room to secure the master cylinder.