putting on speed inc. CAI earlier tonight noticed the throttle body has a hole drilled in it like 17/64th. size. From what i've gathered no previous Gen III TB has that hole drilled in it as its a mod most do after a cam swap. I've been a firm beliver in this RPO LS1 didn't get a revised cam and inherits the same .479/.467 cam vettes and fbodys have. Lutz specifically said changes were made to the camshaft and exhaust amongst 400 changes from monaro to GTO. The hole in the TB and LS6 springs I saw first hand have me curious of what is in our GTO motors.