I have found numerous engine performance tips at speedtweaks.net krcperformance.com
Speedtweaks has the info on the IAT sensor move. Also, racenet.net has the single underdrive pulley for 59.95.
Other suggestions would be a reworked throttle body or 1.7:1 roller rockers, both are $250.
Has anyone put on the Borla headers and were they worth it?