Description MSD83647 by MSD IGNITION Ignition Control Module, Heat Digital HEI Module This all new Heat HEI Module supersedes the current PN 83645. Using upgraded components, the HEAT produces high output for stock and MSD applications plus has a built-in rev limiter that is more accurate and easier to set with the engine running. Works with non-computer controlled (4-Pin) HEI housings. Easily installs to non-computer controlled (4-Pin) HEI housings Built-in adjustable rev limiter can easily be set externally Advanced dwell control for improved high rpm output The Hottest HEI Module you buy-period Produces an incredible 7.5 amps of juice Adjust the rev limiter without removing the cap Fits in stock HEI distributor
