K&N AIR FILTER

With MAF-sensors the general rule is simple - dry filters. Oem paper filters better anyway, I just change it more often for lesser resistance.
 
Like others have said you risk ruining your MAF sensor and then benefits are not sufficient to outway the disadvantages. I fitted one a while ago on my Gen 2 Mini (which doesn't have a MAF sensor). It gave a more throaty sound (but you are unlikely to hear that on a Z4), fuel consumption got marginally worse (but not enough to have any significance) , performance was not changed, insurance went up.

I find cleaning them a pain. The construction appears to be cloth particles held between two fine metal gauzes. They mustn't be blown with an air line and you have to be a little careful washing them so as not to wash away any of the particles. They mustn't be over and under oiled either and oiling them with the K&N kit is not an exact science (squeeze oil out of plastic bottle onto the vanes and look for an even pink colour distribution). They are unlikely to filter out crap anywhere near as good as a decent paper filter.

I wouldn't bother with my Z4. But then again, some love them and swear by them.
 
In resurrecting this post I was referring to the pipercross filter and not the K&N one. The pipercross one is not oiled so no risk whatsoever to the MAF. There is lots of views about K&N but no one previously has referred to the pipercross filter. I didnt expect to add to performance, its just that car felt more responsive and pipercross filter is not that expensive. Probably not conclusive in any way but emission test at MOT were significantly lower than previous years with the standard paper filter.
 
You must log in or register to reply here.
Back
Top Bottom