it lets us use a hotwire mas (the gm 3" or 3.5") which allows us to put the air meter after the bov so that if we want to vent to atmosphere, that air was never counted in the first place so we don't have to worry about running rich when letting off on the gas. in addition, it's more free flowing than the stock air meter, and helps decrease spool-up time

http://www.ramchargers.com/cgi-bin/ncommer...9839&cat2=29840