The LS1 flash tool works by connecting to your vehicle's OBD-II port, allowing it to communicate directly with the engine computer. Once connected, the tool uses specialized software to read and modify the engine's performance parameters.
Recommendation: If you plan more than two engine modifications or own multiple LS vehicles, buying a flash tool is cheaper and better. For a single, mild build, a mail-order tune from a known shop like Frost or Black Bear is fine. ls1 flash tool