I bought my car with the K&N Typhoon installed, however I was unhappy with the performance loss when it heat soaks especially now that it's hotter. I didn't want to shell out $500+ for a Stillen so I modified the existing K&N to a true CAI. I flipped the K&N piping around, so now the 3" side is facing the front of the car. A few additional piping and couplers and voila.