Originally Posted by Todd @ EVO

The OEM airbox is not restrictive b/c of the air filter itself. The restriction is from the design on the airbox in the way the air flows into the MAF area and after the MAF where the resonance chamber is. If you look at the internals of the airbox, the air must make over a 100 degree turn to flow into the MAF tube. It also must flow through a square shaped airbox and flat filter before it makes this turn. In addition if you look at the air filter, you will notice that the dirtiest part of the filter is right in front of the MAF tube. This is also where the OEM airbox has 20 0r so Little holes drilled in the bottom of the box. If this is the dirtiest part of the filter and where the air path is in line with the MAF tube, then a good portion of air is being sucked through these small holes.

I would encourage you to disassemble your OEM airbox and take a long look at its design. I think that after you do you will see more clearly why our High Flow intake system makes as much power as it does. Hope this helps.