I think I can get my paws on the official doc for this unit, but it's in Dutch only - mine is not so good right now. Anyone wants a crack at it for the good of all M3 owners ?
I know it's kind of a shit job, but it would be appreciated. I am myself trying to document "correctly" my special homemade direct injection snorkel (well kit for that matter).
a) Grabs way more air than the Motorsport one (17cm diam)
b) Completely heat insolated (Aluminized polypropylene aka survival blanket stuff)
c) Dirt cheap (but also kind of dorky looking).
Note: A "big mouth" STW spoiler is kind of necessary (you don't want to touch the brake air ramps).