The FAST XDi Street HEI Distributor is packed with high - performance features, making it the perfect choice for any Small or Big Block Chevy engine. Featuring a powerful 6 - amp ignition module that drives a custom - wound performance coil up to 50,000 volts, it provides the hot spark needed for maximum horsepower. These distributors also come equipped with a heat - treated steel gear that is compatible with popular camshaft materials. While perfect as a drop - in, ready - to - run distributor, additional lightweight advance springs and an adjustable vacuum advance are included for those who like to custom tune for extra power and throttle response.