E30 M3 induction question

[Hongkongfooi]

Probably been asked before but I wish to ditch the standard airbox on my M3 for a K&n cone type filter, is this advisable or worth it power wise?


Any good companies worth ordering from?

Thanks in advance

[chippy69]

In BMW Car this month, there is an article on how to modify your E30 M3, maybe worth a read. Some people say just put something like a K&N panel filter on (I have put one on and not felt the difference) but you have to sort out the other end of the breathing as well otherwise IMO it is a waste of time. But I have seen a report that tested the the original air filter againt various aftermarket ones and the original one performed the best but did not last as long.

[AC79xxx]

You may be better off with a sport evo air filter plenum.

The standard K&N filter assembly arrangement may draw in heat from the engine which could reduce the power output rather than increase it which is what I found with my sport evo. I junked the K&N set up and went back to the original kit which draws in air from the bottom of the engine bay (driver's side).

I don't know the cost for OE parts from BMW but an independent supplier should be able to source OE parts (they're advertised in the BMW Car mag).

Alterntively if you're feeling flush there are carbon fibre filter plenums on the market priced around £1k.

[rlk500]

Waste of money.If you have a late Euro spec car, you already have the large airbox that was fitted to the sport evo. The US cars had a smaller airbox arrangement for their daft emuission rules.
In reality, BMW Motorsport did a pretty good job with the airbox, while the AFM is not the most optimum setup for making great power/torque adding a K&N is not going to suddenly release a hatful of bhp. If you want more power a pair of cams and a good custom remap work wonders on the S14 engine, as a starter.

[Hongkongfooi]

rlk500 said:

Waste of money.If you have a late Euro spec car, you already have the large airbox that was fitted to the sport evo. The US cars had a smaller airbox arrangement for their daft emuission rules. In reality, BMW Motorsport did a pretty good job with the airbox, while the AFM is not the most optimum setup for making great power/torque adding a K&N is not going to suddenly release a hatful of bhp. If you want more power a pair of cams and a good custom remap work wonders on the S14 engine, as a starter.

Thanks for that and I will get this months Bmw mag...it was just I have seen quite a large conical filter bunged on the air flow meter with a cold air pipe chanelling cold air from the front and wondered whether it was the answer....by the sound of it no.
And yes the car does have a scorpion exhaust but I might junk that for a more free flow example as I have heard scorpions rob power.