Has anyone slipped a K&N filter into their Countryman yet? I know it's a direct drop-in replacement, so I thought I'd hear more about it by now.

I've had K&N air and oil filters in two of my previous vehicles and gone though cleaning & oiling cycles as prescribed so there is eventually a break-even point associated with the cost of the "rechargeable" variety. The realistic improvements from a $50 filter are likely somewhat nebulous, as I don't recall if it seriously improved mileage or power much -- and that really shouldn't be expected -- but the engines did seem like they were "breathing" a little easier.

With the air box being so far back in the engine compartment, I wasn't sure if it would receive noticeable benefits without also laying in ductwork for a cold air intake.

 

so just read the long archives there on the R55/56/57/JCW boards for gen 2. Opinions are mixed.

Having replaced MAF's on my own car and found the telltale K&N red oil upstream in the intake, they are a big no for me. On one of my cars, the air box was well below the throttle body and intake, whereas the Mini's have them all at about the same height. It had clearly visible very fine red oil streaks (just a dusting) almost a foot and a half after the air box--it's an Audi V8--and the MAF is actually first in line after the air box but well above it). And yes, I have used the filters back to Webers carbs in the mid 70's so certainly know how to oil them very sparingly; I have seen the same issue over time even with the factory oiled K&N filter out of a new box many miles later on routine servicing, including on V6 Audi's and Toyotas as well. Since I installed and then ran them, I knew exactly the history. Net, I pulled them all out over time and added them to the landfill.

MAF's cost many hundreds of dollars--parts alone w/out labor or diagnostics. A few more filters at the margin to me is easy. Actually, simple air hose cleaning of the air filter in between service intervals costs nothing but 15 minutes' time. And even more insidious from experience, the tiny oil vapor slowly fouls the MAF and causes the car to underread the grams/second of air flow. If it sees the wrong air flow, it then provides less fuel, and presumably fights electronically with the O2 sensors that would be seeing it differently. But it still works and doesn't throw a code, so you don't really know it easily. My personal testing using dealer equivalent software on Audi's (via VAG-COM; if only Mini/BMW had aftermarket support remotely like that product...) showed a 20% g/s misread at the MAF at less than 60K miles total IIRC, and 40K miles on a (carefully serviced K&N)--road testing over numerous runs for well over 1/2 hour and simultaneous PC logging of temps, RPM, road speed, gear and MAF flow reading (up to full throttle AT shift points on acceleration) to be clear. That nets to meaningful performance subtract, not add in my book. And yes, instantly after a MAF change and a paper filter, g/s flow reading was restored (rule of thumb being it is 80% of HP in g/s).

Up to you, but I see them as a highly promoted anachronism more for the carb. days, or certainly back to earlier fuel injection before MAF's appeared in the intake tract 10 years + ago.

 

I know it's essentially the same engine as any Mk II or later, but I figured with the "Valvetronic valvetrain", direct injection and different engine compartment (higher bonnet, no scoop, grille and change in airbox/airflow/intakes) there could be some -- albeit very slight -- difference.

Certainly don't discount your red oil findings and I very much appreciate your concise response. Any aftermarket part unsanctioned by the manufacturer is installed completely at the buyer's risk. Especially one that slips into the powertrain of a high tech computer-driven modern car -- has the potential to cause problems and void your factory warranty.

It was really a curiosity question more than anything -- I've had my doubts over the years and while there'll be plenty of dissenting opinions, I don't think I'm going to go the K&N route this time.

Thanks!

 

I just added one to my CM today.

 

i have the vip cai, how often should i clean it? i have maybe 5k miles on it with the cai on.

 

After researching all the replacement "performance" filters I went with the aFe dry filter so as to avoid the oil issue that follows the K&N. I have over 15K miles and have cleaned it once at 12k even though it really didn't need it.

 

there is alot of youtube videos on this topic. i have personally experienced the red filter oil issues so i'm steering away from k&n. plus the temperary improvement in performance is un-noticable to me. fiberglass, paper, foam, they all sound like snake oil salesmen to me because they all have reasons why there filter is better than others. the original filter box pulls cold air from the front of the car. simply a larger intake pipe could improve intake air volume. theoretically. maybe snake oil will make the air flow better/faster into the motor. LOL, just kidding.

 

Nothing but dry filters and stock air box in my car. The engineers got the design right, so don't fool with it.