Personally I'd keep my personal parts away from the air arc. If you insist try 150 amps and 100psi or more.
I was using my air arc today running 3/16" at 100 psi and I had to back off on the air pressure, at 100 psi that rod just started wavering and I couldn't get a steady stream.
weaver,
60-80 lbs of air pressure will be plenty adequate for smaller electrodes.
Have a Great Day, Brent
These are very intresting cause i never knew there was a specific setting for a gouger i just hooked it up and adjusrted stuff til it felt good