Designed for small and big block standard deck Chevy V8, this unit replaces and upgrades stock High Energy Ignition distributors found in 1987-1993 car and 1987-1995 truck external coil applications. Has a machined base for an accurate fit and includes cap with brass terminals for improved conductivity, rotor, and high-RPM control module. We recommend Coil #555-40110 (sold separately) to complement your new high-performance distributor. Will not fit LT1 or LT4 applications.