Quote:
Originally Posted by geeves
|
Power is limited by the amount of air you can get into any engine. Therefore, a better flowing air filter increases horsepower. We have never failed to dyno an extra 4-6% after installing a K&N. That will translate into better mileage but it will NOT be 100 miles a tank and it will depend on which fueling system you have.
K&N's do not filter as well as poorer flowing filters, but the difference is negligible and, if you often drive off-road, you can get their off-road kit which covers the filter and screens out far more debris than a stock filter.
K&Ns are cleanable. So the K&N will last the life of the vehicle.
Now the bad news;
K&Ns are oiled. As with any other quality filter using oil as filtering agent, they can coat an AFM when they are very heavily over-oiled. The easiest way to avoid that is follow instructions carefully, wipe it and then let it sit overnight after oiling.
Additionally, K&N's can present problems for some LRs. The fuel maps on the 3.9s and 4.2s are too lean to begin with. Better airflow makes them even leaner. On the GEMS and Motronics versions, the engine management should be able to adjust to the better flow. If not, you will pick up a fault code indicating a mixture issue.
JB
