Review on Chevrolet Intake System Shield - BLACKHORSE RACING by David Cook

I ended up with a 4" to 3.5" gap as others have mentioned and really think it fits better. Also, someone mentioned thermal foil, so I did the same with the titanium exhaust fairing. Overall there is a nice sound improvement in my 2004 Silverado 1500 5.3L v8 with a noticeable raspy sound at 2-2.5k rpm. The rubber hose definitely made contact with the fan shroud which I easily cut off with a utility knife. The thing is really very tight, so be sure to leave all the clamps loose, just attach the filter at the end and lower into the box. and tilt, slightly raising the air intake. Fits well and sucks air. It also appears to be faster, but you never know if it's just perceived speed.