At the Houston Goat Herd's dyno day at non sponsor can't mention it here speed shop we had about 20 of the herd gather. 04's, 05's stock to sickly modded, underdrive pulleys showing 8-11 rwhp gains. In fact an '04 almost exactly modded like mine, (cam package, tune, L/T, cat back,etc...) put down 8 more rwhp than mine. he had the pulley; i don't 375 vs 383
