This is an AIRAID PowerAid throttle body spacer and assembly for a Ford truck. The grooves in the throttle body supposedly create more turbulent air reaching the intake runners aiding better atomization of fuel resulting is marginally better torque...
I tried a custom made 1/2 inch throttle body spacer on my OHC vtec and saw no performance gains at all. I ran the car with it for some time coz I had plonked it but got rid of it a lil later...
There are whole lot of claims over this product world wide but the only place where it has showed some noticeable gains that I have read is in those all american trucks/jeeps with HEMI's. Claims quote that there is a lil more usable torque generated in the mid range... hehe wonder why they need any more torque, its a HEMI Goddamn it!!! Americans...phew!!!