the m3 is actually seems to be 18% loss on the dyno... but mine is 21% lose..

 

MY stock HP was 236 hp with a kn drop in filter. Then I dynoed my Z with a custom short ram air setup from Frankencar, and got 224 hp then had them make it into a cold air setup and got 239 hp.This was also done on the dyno the same day swapping the parts around. So if i were you i would change your intake, because i know for a fact it makes a difference.

Thanks Glen

 

But i do really hit the position of the injen... it just get wet all the time...