Thought I might share this with you M3ers...
I finally got arount to working on the intake side of my 99 MZ3. I picked up a K&N cone filter and installed it. I spent about 5 hrs making a custom heat shield for it and once I installed the shield, it is very evident that without it, I would probably have lost power. After my first test drive, it was evident that there was a gain. I immediately scheduled a dyno appt. to validate my suspicions. The results are posted below.. I gained approx 10hp and 10 ft lbs of torque over my last run. The first line is JimC, Remus Exhaust, and Underdrive Pulley. The second line is all of the above + the Shileded K&N Cone Intake. The "data" version is posted on my web page.