FAST XDi EZ - Run Distributors come in a convenient package that saves time and space as they do not require an ignition box to fire the coil, while a standard - size cap offers more firewall and manifold clearance than HEI - style distributors. In addition, each billet distributor features mechanical and vacuum advance for easy setup, along with a built - in electronic module that can directly fire an ignition coil, plus provide accurate, dependable and maintenance - free operation. A perfect choice for daily drivers, muscle cars and street rods alike, XDi EZ - Run Distributors are available for most domestic V8 applications.