Replacement air filter element

[wcubed]

I am considering replacing the standard air filter element with a after market unit such as K&N but my locla service rep told me he heard of issues with the K&N filter. Does anyone have any information about this? Alos, any information on other after market filter elements would be appreciated.

Wayne

[Pork Sword]

I've used K&N air filters for years and never had a problem with them. BMC are also good.

[70Sixter]

If you do a search you'll find that a lot of people have MAF problems after K&N install. Probably from over oiling. On the other hand, a lot of folks have reported no K&N problems.

I've used them for years in my -6, but would not risk using them in the Box. Too little gain for even a small risk, IMO.

[wcubed]

Thanks for the info, I figured if someone had problems it would be from over oiling.

Wayne

[berty987]

Though the Kand N filters are a lower resistance to a paper element (due to the filter media being more coarse) the gains are only apparent when the filter is new. The media area on a Kand N is less than the paper OEM , so the dirt particles build up a deeper layer quicker. Once the dirt builds up you have a filter media with similar or greater resistance than the paper original. My suspicion this results in a bigger pressure drop and actual loss of performance. This is why oiled filters need changing and cleaning more regularly than paper ones. For the price of a paper filter and the performance gains of an oiled one , its probably better to change the paper element more frequently. Unless the ECU is retuned to the oil filter air flows I cannot see there being any gain in HP , possibly a minute improvment in throttle response , other than that its just noise and a placebo effect. When the vehicle is in motion and at higher RPM's and speed there is a ram air effect , with an oiled filter there is a risk the air flow is too great for the ECU programmed ranges and so the mixture can run weak. Usually the ECU will retard the ignition to overcome potential engine damage from a weak mixture. The ECU usually has about 5-10 % tolerance in factory settings that can be accomodated in terms of air flow, any more and the MAF will be overange and throw a fault. I've had K and N elements on two other cars, both of which I took the filters out of because the gains were not worth it , the filter needed more maintenance , and the MAF cleaning occasionally. This technology was inspired in the days of carburettors when there were no MAF's , filters sat on top of the carburettor in metal boxes and the induction sound gains were more significant.

Edited August 21, 2009 by berty987