Hey Migraine, the "chip" you are referring to is actually a module that plugs in between the ECM (the computer) and the wiring harness. It alters the information the ECM receives, kind of like tricking it. Generally they change the spark curve (more advance) and the fuel settings (leaner). They can also change the limits for rev limter, speed limiter and shift points, if its an automatic. Superchips and Diablo are just names that come to mind. Hope this helps. Tim.:s3
I'm gonna buy me a Mercury and cruise it up 'n down the road!