Matt, mine was modded as per Kennedy too..I had 258/16's at the time, now runnin 315/17 on H2 rims..Overall I still get over 17mpg in the city, so I can't complain..:smilewinkgrin:
FWIW...I've asked a couple CAi makers to show flow, and hp improvments if any..never heard 1 word from them...I won't name the makers, but all have heard of them.
Also, there was a test done re: cai's and the Duramax stock airintake with the ac delco filter..guess which one won..:biggrin5: