High Energy Ignition Coil For MEGA SPARK 4 IGNITION COIL Mega Spark Coil for use with Lumenition Optronic Ignition System. (Including 1.5 ohms ballast resistor) MS4 has been selected to match the requirements of both the ignition system and the target vehicle applications. It is a direct physical replacement for the original coil in most cases. An original or supplied 1.5 ohms ballast resistor must be used.