Originally Posted by e46kyle
We need to email supercharger companies and let them know they are losing sales because of this, so they can get it carb legal
It's because California wants to use the oem air box with the oem air filter that has a charcoal filter in it. It's easy to do when you have a roots style manifold blower like magnacharger, but not with a centrifugal blower when it takes up that space. No one makes a roots style for the m3 because the throttle bodies connect to the manifold with hose clamps. Those clamps are not strong enough to keep the plenum from being pulled down by belt tension.