Does anyone know how much vacuum a chevy combo fuel pump / vacuum pump makes at idle. I;m referring to the type that runs off the cam or fuel pump eccentric. I'm upgrading to a bigger cam for more pow-wa but will loose vacuum for my brakes. I need about 17 inches for my brakes to feel right.
Are you talking about a fuel pump that would run a vacuum wiper system? Would a vacuum reservoir help any?
yes, the type of pump chevy used for vacuum wipers. I don't want to put an ugly tank somewhere and I really don't have the room for at tank or eletric pump. I have a electric fuel pump in the back of the vehicle so my fuel pump spot on the block isnt being used. Vacuum lines down low and out of they way seem ideal to me. I;m looking for an active solution that doesn't have my car/life hanging in the balance relying on a made in china plastic check valve.
It will take some time to build up vacuum with the fuel pump unit as it isn't real high volume. The brake booster has the large reservoir that will give you a couple of brake applications. You might be able to use the fuel side of the pump also to increase the volume. Connect a vacuum gauge to it when running to see how much vacuum it pulls. You could use a booster that runs off a power steering pump instead of vacuum.
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