Aftermarket air filters, less restriction = more dirt?

Bimmer 808 · 07-21-2015, 01:14 AM

So I was thinking about replacing my stock air filter with a K&N drop in. Did some searching online about the pros and cons and came across these two sites that have supposedly tested different filters.

http://www.bobistheoilguy.com/airfilter/airtest3.htm

http://www.nicoclub.com/archives/kn-vs-oem-filter.html

I couldn't find anything about this topic in the forums. Bottom line from these sites is that less restriction = a dirtier engine. Are we increasing the risk to our engines by installing these aftermarket filters, DCIs, CAIs, etc.? Is the juice worth the squeeze?

xcusem3 · 07-21-2015, 04:39 PM

Have you ever taken your intake system apart, post turbo? (FMIC, CP, Intake etc.) If you're not familiar with direct injection cars, the amount of oily nastyness in there will shock you. I don't think we need to worry about drop in filters passing microscopic amounts of dirt into the engine, just my $0.02

07-21-2015, 01:14 AM	#1
Bimmer 808 MT or bust! 170 Rep 289 Posts Drives: 2010 E90 335i M Sport, 6MT Join Date: Nov 2009 Location: Alexandria iTrader: (0) Garage List 2020 X3 M40i [0.00] 2015 M235i [0.00] 2006 330i [0.00] 2010 335i [0.00]	Aftermarket air filters, less restriction = more dirt? So I was thinking about replacing my stock air filter with a K&N drop in. Did some searching online about the pros and cons and came across these two sites that have supposedly tested different filters. http://www.bobistheoilguy.com/airfilter/airtest3.htm http://www.nicoclub.com/archives/kn-vs-oem-filter.html I couldn't find anything about this topic in the forums. Bottom line from these sites is that less restriction = a dirtier engine. Are we increasing the risk to our engines by installing these aftermarket filters, DCIs, CAIs, etc.? Is the juice worth the squeeze? __________________ 2010 E90 335i M Sport, MT - BMW PE; VRSF 7in HD; RB PCV; VRSF CP; Turbosmart KPB BOV; M3 Cowl; VRSF Cerakote DPs; Carly coding; ECS Scoops; Ziza interior LEDs; Fuel-It! Bucketless; Diff lock down brace V2; MHD E60 Map from BQ; Mishimoto OCC; Fuel-It! Ethanol Sensor; Apex 18x9 ARC-8's; StopTech slotted rotors; HPS pads; ECS brake lines; MMP turbos, inlets, outlets; 034 mounts; Kumho PS31s; BimmerLife coils
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07-21-2015, 04:39 PM	#2
xcusem3 Lieutenant 457 Rep 539 Posts Drives: 2013 M3 Join Date: Jan 2015 Location: Calgary iTrader: (0)	Have you ever taken your intake system apart, post turbo? (FMIC, CP, Intake etc.) If you're not familiar with direct injection cars, the amount of oily nastyness in there will shock you. I don't think we need to worry about drop in filters passing microscopic amounts of dirt into the engine, just my $0.02 __________________ CP-E DP's / Remus Race / ETS 7" FMIC / AFE DCI / Cobb V3 / ETS CP / HKS BOV
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