So I am guessing you made the pulley smaller? I did the same thing with my Cobalt, dropped the pulley size and had bigger injectors thrown on along with a tune from GM. Gained some good power out of it.
2013 2SS Hot Wheels Edition 727 of 1524
w/ Dual Mode Performance Exhaust, Nav, and
DELIVERED APRIL 22nd, 2013 and enjoying every minute since!
Cold Air Inductions CAI, CNC Ported Throttle Body, Elite Engineering Oil Catch Can, Smoked Spyder LED Tail Lights, 12" JBL Sub, JBL Amp, Stealth Sub Box, American Racing LT headers and hi-flo cats, Tuned by Davenport, Custom painted interior pieces, Custom painted hood liner, Niche Targa M-130 wheels, LED side markers