HEI Distributor - Chevorlet SB / BB (55-87) A new HEI Distributor with electronic tachometer output that generates 65000volts with the built in ignition coil. Hei distributor is a strong distributor with a built-in ignition coil. It has an aluminum housing and double steel bushings. The distributor has a strong ignition amplifier and generates 65,000 Volts. It has solid brass contacts and a simple 1-wire connection. The gear is made of sintered metal. Fits engine: Chevrolet SB 55-87 Chevrolet BB 55-87 Installation: BAT - connected to ignition voltage TACH - connected to tachometer if one is to be used. Length from heel/stop to bottom : 195mm NOTE The electricity in cars with original ballast resistors must be rewired so that the new ignition coil receives ignition current directly from the battery. Instruction