Originally Posted by utkinpol

that is identifiable - with K&N if that is the conical one inside of engine bay timing goes bananas when it starts to suck in overheated air from engine compartment. those conical filters that are inside of the bay only work well if it is a forced induction car, turbo or supercharger, and all air goes in via intercooler so it does not matter if you have proper CAI or not. for NA cars it is critical to suck in all air from the outside to maintain timing.