surge happens under 2000 RPM with mine. and when it does it, it's only at about13 PSI. and actually when it first did it i was running stock. and i didn't know what the hell it was! i just have to move my shift points up a few RPM's

Its more luck of the draw Ive had 2 7.3s both were 01's, my first one never surged and the one I have now does it all the time. Kinda goes to say if it aint broke dont fix it.

but you can get rid of it easily on the 99.5- 03 with a ported compressor housing. the e 99's are really a luck of the draw. mine does it and my old boss with the identical truck doesn't.