Joefish, there are some rather large threads on reefcentral about ASM skimmers and mods you can do to them. There are tons of cool options to make them more efficient, including pump replacements. I've attached the link below to their useful ASM threads. It's helped me out a lot with my G3 so I hope it does the same for you. Good luck and happy reefing!
http://www.reefcentral.com/forums/sh...light=asm+club
ASM Skimmer FAQ's - Reef Central Online Community