A capacitive discharge ignition designed to complement electronic fuel injection systems.; MSD now offers the perfect addition to your MSD Atomic EFI or other aftermarket electronic fuel injection, the 6EFI Ignition Control. The 6EFI is designed to work in harmony with electronic fuel injection systems and comes with detailed wiring instructions making installation a breeze. Increased throttle response, smoother idle, quicker starts and full ignition power throughout the entire RPM range are all benefits of adding a 6EFI ignition to your fuel injected engine.