Review on Enhance Engine Performance with the Airaid 200 543 PowerAid Throttle Spacer by Robert Espinoza

Can't tell if it makes much of a difference as I installed it with a K&N cold air intake. I hear a soft whistle. This is clearly not a turbo sound. With that and CAI, the fuel economy on my 2017 Silverado Z71 dropped from 16.5 to 18.5. Easy installation. Just make sure the manifold bolts are evenly and criss-cross tightened (i.e. don't fully tighten one if the others are loose).