[psyco66]

Today I pulled the air box in the center of the engine off of the truck. The box that has 6.6 on it. When I removed the air box I put a plug in the hole. The plug is two peaces of metal with a peace of rubber inbetween it and a bolt with a wing nut on it. The hole is two inches wide. I put the plug in and I tightened the wing nut. For added security I put a 5/16 lock not onto of the wing nut so it will not back off. I then reinstalled the air box cover thing. The turbo whistle is way louder when I let of the fuel pedal. Hope this helps you guys that want a louder whistle. If anyone needs pics let me know I can get some. It is realy easy. Went to the hadware store and bought the plug for 3.60 and it took all of about 5 mins put put in. If you go to the hardware store look in the plumbing section for the plug like I described.