Which air filter?

[WorldClassAccident]

It turns out the company I bought my K&N air filter kit has disappeared so I am chatting with Paypal to see how I get my money back :-(

This does give me that change to choose a different type of filter if I want.

The K&N ones are oil soaked and this can affect the MAF over time. Having just been surprised by the improvement I gained simply by spray cleaning the MAF (https://www.youtube.com/watch?v=fzKCVObJt5g) I am now wondering if K&N is the way to go.

I plan to replace the standard BMW airbox with a more free flowing one and hopefully rig up some kind of cold air intake system (possibly using a flowerpot).

Are there non-oil based cone filters?

Are there other options?

Anyone got thoughts on what is best?

[garyh]

Just give it a blow...

[landmannnn]

The k&n filter maf issue is a bit of a myth, mafs need cleaning regularly anyway.
What isn't a myth is the lack of improvement from a k&n, the improvement in air flow is minimal and sometimes worse than standard.
Chopping off the air box and attaching a pipercross cone is nice and simple, if a little noisy!

[y cymro]

As I've said on your other thread, the z3 air box offers an inefficient path for air flow so there are opportunities to increase air flow, and therefore power. But, whichever filter you chose you must protect the filter from engine bay heat, and you must provide ample cold air.
Treated paper (like the K&N) and foam filters like Pipercross rely on oil to help particles adhere to the filter. The problem is that people over-oil them and then moan that their MAF is jiggered. You don't need to oil a new filter.
I bought an ordinary Pipercross cone filter from eBay for less than £20. Because I've built an airbox for it from a 99p Tesco flowerpot (and an hours work!) and provide copious cold air, it works well, sounds great, and definitely makes the car quicker over 5 1/2 thousand revs - proven using my Acceleration Retardation System Evaluator - whereas the standard car starts to struggle at high revs.
If I was doing it again, I'd buy a Pipercross filter with the aluminium spun bellmouth, though these are 60 quid. Check the sizes but something suitable may be this in eBay 370892987954.

[WorldClassAccident]

Ordered another K&N but from Demon Tweaks this time. Hopefully they won't disappear before they ship it.

I will be 'flowerpot charging' my induction system.

Clean MAF - Damn right. Improved by over 1/2 a second 20-80 times without any fancy filters, just a squirt of cleaner. Very pleased

[IanA]

Would something like this suit?



Described as a MAZDA MX6 2.5 V6 93-97 HIGH FLOW COLD AIR RACE INDUCTION INTAKE 3" FILTER KIT currently listed under eBay item number: 350794802439 for £39.99.

[IanA]

That sort of dry cone filter usually sells for £12 at shows.

[y cymro]

Originally Posted by IanA

That sort of dry cone filter usually sells for £12 at shows.

True. My local Motorworld has them for around that price too. And you'll still need a flowerpot/paint tin or similar to keep it all coolish.