Quick question.... If u dont get a intake polish how do you lose power even though you get more air flow?? Is that a proven fact. I believe you guys just want to know why. Thanks.. You guys have been so much help

 

Ok, you buy a 70mm Tb, and you have a 99-04 which has a 60mm opening inside the upper intake, so that means you now have a ridge that forms from the larger throttle body sudenly going into a smaller hole. This causes turbulence all around the opening which inturn actually restrics airflow, so that's why, at th very least, you need to port match your upper intatke to the TB, you don't neccessarily need to polish it, although it wouldn't be a bad dea, but you will need to port it out. I still reccommend getting a powerpack from supersixmotorsports.com, becaues without a ported upper and lower intake, along with ported heads, and a mild tune cam, all other mods won't add that much HP, well except a S/C or a T/C, both of which require a port job, a cam, and forged internals, for maximum performance gains.

 

if you're gonna spend the time porting it, you might as well polish it, all it takes is 150 grit sandpaper