Hello
The K&N do flow more then most airfilters on the marked. But they used the cheapest to compare. I remeber the factory used K&N on rallies as they will still flow even with dirt on it and you can wash it so your spare parts box is smaller.
A german Automagazine made an comparetest on a Diesel engine to find out whats up. Power increase none but engine had siliconose after 50 000 km, in words to much sand landed in there.
So cleaning and renewing the oil should be in much shorter intervalls then K&N says.
Well made with one car and a Disel you can´t generalize it.
On Ferraris the K&N allways give improvments as the original Filters are dirt cheap ( But sold oppesite ) and have on old cars a 5000 km Change intervalll ( Ever done on a 365 GT/x ? 5 hours work for 2 filters )
Grüsse
|