K&N
Who has replaced their stock air filter with a K&N? Are they really better? Improve performance, gas mileage, etc.
Forum Discussion
Bamaman1 wrote:
They're okay on gas engines. But they're totally ineffective on a diesel engine.
Diesel engines' high compression also make the intake air act differently than a low compression gas engine. It sucks dirt right through a diesel K&N air filter.
On a gas engine they don't make any difference at all performance-wise until the throttle is all the way open. As long as the throttle is, well throttling, the pressure drop across the filter is insignificant.
Diesels don't have a throttle so they ingest a lot more air than a gasoline engine of the same displacement naturally aspirated. Add a turbo and they are moving up to 3 times the air. Compression ratio has nothing to do with air flow on the suction stroke.
I agree with many here in thinking the K&N is a waste of money and has the potential to do more harm than good.
