gruppe m intake stats...
 

stumbled upon this website and found this thread. slightly pretentious forum if you go to main page...<ul><li><a href="http://www.teamspeed.com/forums/performance-series-audi-models/3077-gruppe-m-intake-b7-rs4.html">http://www.teamspeed.com/forums/performance-series-audi-models/3077-gruppe-m-intake-b7-rs4.html</a</li></ul>

Now all we need is an independent dyno...

You can disregard this dyno graph...
 

If you extrapolate the power axis it is showing something in excess of 400ps at the peak of the curve.