turbo overboost

i have a 1987 daytona 2.2 turbo, when the turbo kicks in , the gauge goes way past 15 lbs, then the car shuts off for a moment,i just installed a mopar performance computer 3 weeks ago, no problems. what could cause this?

I raced a 87 shelby turbo, and if your past 15lbs of boost your asking for trouble. All the MP computer does is give you constant 12lbs of boost. The normal computer gives you 12lbs of boost for a short time and then backs it off to 9 lbs of boost. If you keep it at over 15lbs of boost you will blow a head gasket and hopfully that is all. As far as it shuting down the computer will also back off the timing that maybe what you are feeling. You should reset the computer by disconecting the small wire that comes off the battery, leave it disconnected for about 2 min and then reconnect. If you don't the computer "remembers" that you over boosted and won't give full performance for about 20 or so restarts of the motor.