The handheld programmer requires just four bits of information to be inputted into the ECU. Holley has pre-loaded base programs, but the handheld also allows certain parameters to be adjusted manually for specific applications, like desired idle rpm, and different air/fuel ratios. The four questions for the setup Wizard are: What is the part number of the system purchased? Is it a small-block (under 409 ci) or big-block (over 410 ci)? What type of camshaft (stock, mild, performance, or I don't know) is in the engine? And the final question, will the ECU will be controlling the ignition timing?