Moates is a company and a guy. They make devices for tuning a variety of cars. One of the devices they make is named the Quarterhorse. This is a device (aka Chip) which allows you to tune an EEC-IV computer as well as data log the information the computer is using to make decisions.
To leverage the features of the Quarterhorse device, you will need to purchase software (Binary Editor) and a strategy (specific to your EEC-IV). You will want to use a wideband on the dyno or purchase a wide band for yourself if you want to tune yourself.