[Koldun]

I've read quite a few old threads on the topic of air intakes, but they always seem to boil down to pissing contests and arguments over warranty, and creative interpretations of the Magnuson-Moss act.

From my prior reading and the dynos I've been able to find, it seems the majority of the gain comes from the filter. So with MS products, for example, a drop on filter advertises 6-7HP, with the full intake adding about 10. A number of people have also noted that after 2010, the M3 comes with the much less restrictive euro air filter, so the gains would be smaller still. Furthermore, most of the gains occur at high RPMs/high speeds.

So putting warranty and brand preferences aside, would it be fair to say that a complete intake kit with filter, scoops and arm for a newer model M3 will give roughly/no more than about 5 extra horse power at the upper rev band, or about $100/1HP?