Holley’s 1,000-cfm, carb-style throttle body (PN 112-577) tops off the 427, and the groundwork for ignition is laid with the installation of the Holley EFI DIS hardware. A distributorless ignition system basically replaces the engine’s mechanical distributor. In this case, coil voltage will be managed through the Dominator ECU. Notice the cam-position sensor mounted in the distributor bore? While this magnetic sensor is required, it is not available through Holley EFI, but can be acquired through such companies as AEM and others.