The J2 or EPP will lower WGDC I believe by about 8%. When you add the new IC it makes the turbos have to work a little harder bc of the increase in volume so they WGDC increases. So to its credit...bc it decreases WGDC it clearly flows more air, more efficiently than the bottleneck stock plastic parts. I'm interested in the new Intake for the increase in air flow, decrease in WGDC and so I can spray each turbo with something(no2) through the new Intake since it feeds each turbo separately. I hear you can really hear it....i like more noise so thats also a plus imo.