Inside the ECM there is a chip. Look for the little door with a screw in it. Below that is the chip. Different years have different chips, baud rates, fuel maps, etc. A 305 chip from 85 TPI has a way lower rate from an 86+ chip. You would need a chip with a new program (burned chip) to do the stuff you want or change the ECMs outright.
Do a search on the net for OBDI (On Board Diagnostics One). Or you could also read up on this site, its how I got started to understand the whole Fuel Injection stuff. Its alot to soak in...