For many years NGK Spark Plugs has been firing racing engines throughout the world. NGK Spark Plugs has become an icon in spark plug technology. To withstand the severe conditions that occur in racing engines, NGK Racing Spark Plugs feature electrode materials and configurations as follows: Electrode materials - Many use precious metals such as platinum or gold/palladium for greater durability and lower voltage requirements. Electrode configurations - Fine-wire center electrodes provide better sparking and enhanced ignitability. Fine-wire ground electrodes further improve the ignitability of the plug. Insulator configurations - Special configurations are used for the insulator noses to improve throttle response.