Again, for your car, the plug in type of "upgrades" are simply resistors that trick the ECU into running a little bit richer. You might feel a little more pep on your butt dyno, but over time it will damage the car.
The only type of upgrades you should be looking at are ECU reflashes. You'll have to remove the ECU and send it off, or go to a dinan dealer and have them do the flash for you. |