When i cut my bumper like the stillen front fascia i noticed a 2-3 degree drop in IAT. IAT is now only 6-8 degrees above ambient with the stillen Gen III. It might be more benificial in getting the stillen fascia because it already has all the vents and bigger grille, minus the vents for the upper part of the radiator.

http://i825.photobucket.com/albums/z...psq5fek5bf.jpg

Between installing my Stillen front bumper, my JWT pop chargers and switching to Valvoline High Performance 5w30 my oil temp is about 20 degrees cooler than last year.