[Ronebo69]

How hard is it to swap out stock for a K&N filter

[Vudumonkey25]

Originally Posted by Ronebo69

How hard is it to swap out stock for a K&N filter

Just a drop in? Open air box, remove stock, put in drop in. Done

[yanks1]

I'm thinking of doing same

[Saturns]

Does anyone have the correct K&N part number for the m240i. Looks like online they have 2021. But does that work with the 2023?

[BG42]

If it's in stock local to you just pop yours out walk in and verify if it's the same.

[M240SLC]

Originally Posted by Saturns

Does anyone have the correct K&N part number for the m240i. Looks like online they have 2021. But does that work with the 2023?

Should be 33-3136.

[SammyAlipour]

Originally Posted by Ronebo69

How hard is it to swap out stock for a K&N filter

Don’t use a K&N filter or any sort of cotton air filter. They don’t filter out anything and you get 0 power gains. Feel free to watch a K&N vs paper filter comparison video. The only filter which is relatively safe are the AEM dry flow filters. I can happily share a video or two if you’d like.

[old_man_feet]

Originally Posted by SammyAlipour

Don’t use a K&N filter or any sort of cotton air filter. They don’t filter out anything and you get 0 power gains. Feel free to watch a K&N vs paper filter comparison video. The only filter which is relatively safe are the AEM dry flow filters. I can happily share a video or two if you’d like.

Not OP but I'm always up to learning something new. Can you please post what you have? TIA

[Rdurty2]

Originally Posted by Xspeedracer

Do not use a K&N air filter the oil from the filter will get on the MAF sensors and can affect performance, the stock filter Is more than adequate

That is incorrect for our cars. The gen 2 B58 does not have a maf sensor like the gen 1 did. The sensor on the intake tube is just a temperature sensor.

[redcars]

Just take your existing one out and check for part #.

[SammyAlipour]

Originally Posted by old_man_feet

Not OP but I'm always up to learning something new. Can you please post what you have? TIA

Sure! Here is a YouTube video that has great info!

https://youtu.be/sJ3L-E-ufYo

You can also look up “K&N filtration test” on YouTube and find more videos. This is the same problem almost all cotton air filters face. The only filter that I’ve seen test well other than paper air filters is the AEM Dryflow filter.

[Rdurty2]

Originally Posted by Xspeedracer

So when I look up a 2020 m2 I get a MAF Sensor listed

Why are you looking at an m2? This specific section you are posting in is for the g42 which is m240 and 230

M2 has a completely different engine compared to the m240

Also a 2020 m2 wouldn’t even be correct if you were posting in the correct g87 section is a 2020 is previous gen.

[Rdurty2]

Originally Posted by Xspeedracer

Well in my experience with K&N Air filters I think I know a bit more about the issues they cause over time it doesn’t matter what car it’s used in it still causes issues over time compared to the dry factory air filters

ok, but the m240 does not have a maf sensor.

I agree that over-oiled filters can cause issues with maf sensors but that is a moot point with the b58 engine.

[Xspeedracer]

This is a really well done explanation of differences between some name brand air filters and the ability to protect your engine https://youtu.be/YypvDEQyNBY

[XC3LLR8]

I always get a kick out of the K&N haters. They remind me of the wheel spacer haters.

I have one in the G42 and one in my wife's Mazda. Takes about 2 minutes to install.

Watch these videos and make your own educated decision...

[Xspeedracer]

Well the wheel spacers do add load to the wheel bearings as you move the load further from the load center of the bearing. Ask a mechanical engineer sometime it’s always interesting to learn something new, as for K&N great idea perfect for a race cars not so good for long term street use

[old_man_feet]

Originally Posted by SammyAlipour

Sure! Here is a YouTube video that has great info!

https://youtu.be/sJ3L-E-ufYo

You can also look up “K&N filtration test” on YouTube and find more videos. This is the same problem almost all cotton air filters face. The only filter that I’ve seen test well other than paper air filters is the AEM Dryflow filter.

Hha, I watch PF all the time but I had not seen that one. Thanks again!