The problem with a chip for the normally-aspirated 2.8 (whether 30v *or* 12v) is that you are limited by the amount of air the car is breathing. You can get much more from forced induction and remapping ECU (read as superchargers or turbochargers). Without improving the breathing of the 2.8 you are going to get minimal performance gains from any chip. You could have heads and intake ported and polished, have performance camshafts installed, a filter and airbox mod and a new exhaust. With those upgrades, and a chip....you will see very good gains. Also, you will have done the work internally and therefore they are strong and reliable.
Just my $.02
-Cathleen

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