K&N filter installed

I was going to get a power pipe for my cobra, I took the old filter out to look at it. Yep, stock paper filter. It was dirty but not filthy. I looked in the fender well and there is some 'stuff' in there. It looked crowded in there, so I decided to just get a K&N and for go the power pipe. I just couldn't see where there would be much difference. After the K&N install the car feels much stronger, maybe its my imagination. I was powershifting at 6500rpm, but tonight it pulled past 7000 and I backed off for safety ...it was still pulling(amazing). I'm sure I'm not ready to try that T/A again, then again...