Dave c did a good job expaining. I was in on the ground floor of Polution testing control and reopair and have taught the subject to tech as well as update courses for industry. (Had one of the first gas analyzers east of the big smoke (TO or Toronto as some call it) If the air pump works and you want to use it other than the power it takes to turn the pump which would be tiny (less than 1 hp I believe) it does not affect perfomance one way or another. As Dave stated it injects the air into the exhaust so it is an "after the fact" system and has diddly -squat to do with what goes on INSIDE the motor. Don Blood pressure low? Not awake yet? read Dons rants and get you self going again http://seniordragster.bravehost.com/OLDTECHNOLGY.html [Non-text portions of this message have been removed] ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html.