I have an Ingersol Rand Model B compressor that I am using for the plasma. I have had it for years and it has had a couple of motors on it in the time I have had it. I have been looking around to see if I could find out what the motors HP and RPM should be and what the speed of the pump should be, but so far not really come up with much. At the moment it has a 920 rpm 1Hp motor but that is too slow. It is not keeping up with the plasma at the moment, from what I have seen it should be about 4 or 4.5 CFM and the plasma draws 100LPM, so about 3.5CFM if my calcs are correct. Anyone know what motor RPM should be on this or even better what RPM the pump should be?