Originally Posted by +fireamx
OK......Well the only reason I asked is because it seems like everybody uses 3" diameter plumbing, but all the incoming air still has to squeeze thru those small holes in the core support. I figured the efficiency of any CAI comes down to how much CFM it flows, its flow characteristics, and the smallest passage way the air has to travel thru that's all.
After you remove the original inlet adapters in the core support you can fit a 3" tube on the right side and a 2 3/4" on the left side. You must also remove the hood cable cover to squeeze in the L/S tube. This is what I have on my car now (NW Dual CAI)