for Porsches is that there seems to be a supposition that the Porsche engineers either don't have the time, money or smarts to get every last bit of HP out of their own power plant. That strikes me as just a bit presumptive.
Automotive engineers, I think, try to design a powerplant that will --hopefully-- provide maximum output over a range of operating conditions and operate reliably
for an extended period of time.
K&N's goal is a bit more modest; it markets a product that lets more air through an automotive intake system than a stock paper filter--but with the downside that it doesn't filter as well. Given that the HP increase is marginal, if any at all, this strikes me as the worst of all automotive bargains--paying more for less with a big potential downside.
Or to put it anyother way, if the product was so great that it could magically add 5-10HP with no downside, wouldn't you think porsche would make it the OE air filter? Seems like a much easier way to get that last 10HP out of a car rather going from vario cam to vario cam +.
Then again, it's your $
