94 Z28 Cutting out problem, Please Help!

My 1994 Camaro Z28 Cuts out really bad through all the rpm ranges, it gets worse as it get warmed up and the longer it is driven. It has a new Optispark, Plugs and Wires, Fuel Pump and MAP sensor. The car has SLP Loudmouth exhaust and K&N Cold air intake. It was sending out a code for the MAP sensor, I replaced it and now it is running worse than before. If you have any information that could help me, I would be very greatful. Thank you.