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Hello All,

If you want to have a real air filter go the carbon fiber way!
It's the only way to have proper cold air into the AFM, other wise you will have a more eficcient airflow, but with warm air coming from the engine bay!

To have a proper air intake you will have to get an air tunnel from the front grille directed to the air filter and with a carbon fiber case, such as these ones from BMC www.bmcairfilter.com

And they are available to our cars.

Regards
Frederico

That's why my car has a shield between the radiator & engine and the filter. And the front grille opened up a bit more like between the headlights!

what always amazes me is the fact that these cone filters are fitted in such a way that after the bonnet is shut, half of the cone is almost blocked off by it...
I am a believer of the original setup with a new / clean OEM filter. After all it seems to flow enough to get 238 bhp out of it.

Yep, that's why my cone on the 325i is pointing downwards and why I've opened up the front grille more. On the 325i that is. If I want to improve further I guess I should remove the left front high beam unit I guess. Using a A/F ratio meter I should be able to adjust the mixture but the problem is the difference in air flow at different speeds. That's why it'll stay like this for now.

On the 320iS I run the stock intake box and filter. Not sure if changing to the larger lower air box will give any gains... any experiences there?