[SO8]

Has anyone with a mapped 335i then put in a K&N / Pipercross / ITG panel filter or the like ... and if they have, have they noticed any difference ?

I know on a normal car they will make little or no difference but wondered on a mapped 335i ?

I am only interested in views on a straight replacement panel filter not a full 'cone' type filter kit.

[idnan]

I've had the K&N panel filter, a £400 enclosed filter with new airbox etc, dual cones with heatshield and ordinary dual cones.

Apart from the difference in noise, I've not felt anything in terms of performance between them at all.

That was all on a car with full engine mods including hybrid turbos.

[Nobber]

Agree with idnan on this one. Little to no difference with anything I've ever done filter wise on any modded car. In fact I did side by side runs in my S3, one with std airbox, std airbox with Jetex filter and one with ITG.

There was absolutely no difference between the panel filter/stock but the ITG interestingly did 6bhp LESS but 15 lb/ft MORE torque.

The only 'advantages' of a panel filter imo are that you can clean it rather than having to replace it like you would a paper OEM filter.

[AWBimmer]

Yes Nobber right ref: cleaning instead of replacing. Sometimes cleaning using the oil does attract more dirt and residue to be stuck in between the grooves, but I could be mistaken. Atleast it's what I found in my previous BMW. Currently I'm happy to run a stock one and replace every year or two..

[gangzoom]

I bought the fancy enclosed filter/airbox from idnan....Absolutely no difference in power/performance, might put the stock box back on next time I do any work in the engine bay.

[Ibz82]

I have had dci previously, have k and n drop in now along with my jb4 downpipes etc...
In my opinion the drop in is far better than the cones.
Reasons, noticed a lot of torque difference at low revs and much more smoother.
There is an argument that the dci allow more air etc... But in my experience this isn't the case, even terry at burger tuning admits in his write up on the intakes that you may have better results with an adapted drop in filter! Is that an aftermarket airfilter or adding scoops etc but there is Definatly a something in what he has written in his write up.

[SO8]

Thanks for the replies. I had a look at my paper filter and it is quite clean so probably changed at the first service 8K ago ... guess I may leave it alone for the moment.