Edelbrock Ignition Coil #22746 is a high-output oil-filled cannister-style coil recommended for use with Pro-Flo 4 EFI applications and is also compatible with other aftermarket EFI and ready-to-run distributors. Features include a higher winding ratio for more voltage build-up and higher spark energy when compared to competitor coils. The main difference between the Edelbrock #22746 Coil and other cannister-style coils is the primary resistance of 0.7 ohms compared to 0.4 ohms for standard ignition systems. A primary resistance of 0.7 ohms is the minimum that we recommend for use with Pro-Flo 4 EFI systems.