Yeah, I already had the bungs pressed in for the mustang injectors so I decided to bust out the hole saw and match the intake to the runners. Plus- it's a pretty cost-effective way to get a better flowing intake. I didn't go crazy on the size- mine's around 4 inches on the inside and tapers down to force air back as opposed to the usual 5 inches without a taper. I didn't use velocity stacks- no need. This shouldn't rob me of HP like a lot of the cosmetic one's do. Plus my 90mm Accufab Throttle body will fit perfectly.