[KingLT1]

I am running a 3.375 with Big gulp on E50 but I have a full fuel system. I can hear the supercharger quite a bit now. The Big Gulp made the biggest difference because I had the regular RF intake prior with the same pulley. You will likely need LT4 fuel system to run a 3.375 and more possibly more octane then 93. The 3.5 pulley and big gulp will put you right at the edge of the fuel systems capability on 93.