I am attempting to resurrect the gMax Mitsubishi MU-2B that was abandoned when the Simubuild group broke up.  I have updated Michael Verlin's nice FS98 panel for that aircraft, installed a Garmin 530 GPS unit (mainly for keeping with the visual character of the original panel) and have installed a 737 ASI (400 kts).  In attempting to increase the aircraft speed to the mid-300's per specs, I am getting an overspeed warning at about 250 kts.  Using FDE, my max speed setting in the flaps section is 380.  What determines the trigger point of the overspeed warning, the .air file parameters (which ones) or the ASI gauge or a violation of some critical engine parameter?  I've looked in vain for a tutorial on tweaking .air files to no avail.  Sorry, I'm a novice at design yet... ???

Many thanks, Ian!  Hope I can contribute here one of these days rather than asking for help.   

Oops!  Sorry 'bout that.     I had surfed to your recommended web sites and noted Ian's name several times and had it "on the brain" I guess.  BIG help, Felix!  Thanks.  Just need a  lot time and a pot of coffee to get through all the details and tweak away...  The aircraft is a bit of a challenge, VERY fast for a TP, narrow wheelbase, weighted wing tip tanks, no flaps...a lot of unconventional things which, added together, cause rookies a lot of headaches.  Maybe that's why Simubuild gave up on the MU-2B model....