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MSD 83647 Heat HEI Ignition Module

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MSD 83647 Heat HEI Ignition Module
Product Video
MSD 83647 Heat HEI Ignition Module

Click image to enlarge

Follow along as an MSD HEAT HEI Module is installed on a classic HEI distributor.



Q & A

What's in the Box

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 distributors

547-83647 Instructions (PDF)

MSD Tech Bulletin (PDF)

MSD Rebate (Link)


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Ceramic Wire Core Cut-A-Way (Link)

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MSD Rebate (Link)

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MSD Rebate (Link)