Brians right there - it doesn't surge at all and it does a wonderful job dealing with low rpms. When I tow @65 I am only turning 1750 rpms, and regardless of fueling box situation this turbo has had no problems running with a load at that rpm range. I just set the cruise and go and the turbo has been happy to work for me. Yielded a milage increase too. Less drive pressure, I think from the larger housing, plus possibly a cooler charge? Been a good turbo, and has only barked hard once or twice maybe. My fault when that happened.