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MSD 83647 Heat HEI Ignition Module

Specs
GTIN Code:
085132836475
MSD 83647 Heat HEI Ignition Module
VIDEO
MSD 83647 Heat HEI Ignition Module

Click image to enlarge

Details

Reviews (8)

Q & A (2)

What's in the Box

Info

Save BIG during Happy HolleyDays! For a limited time receive up to 20% off select Holley, Demon, Earls, Flowtech, Hooker, Mallory, Mr. Gasket, MSD, NOS, Quick Time, and Weiand products. Sale prices valid thru 12/31/16.

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)

 

Customer Reviews

Rated 4.5 out of 5 by 8 reviewers.
RATING BREAKDOWN
8 reviews
5 Stars
5
4 Stars
2
3 Stars
1
2 Stars
0
1 Star
0
RECOMMEND THIS PRODUCT:

msdstinks
Verified Purchaser
usa

not worth the hype

September 27, 2016
so far no advantage to a stock GM module on a 500+hp carburated car... except having a rev limiter. car might start a very little bit better but idle seemed weaker & no noticeable difference in any RPM up to 6000 vs the stock module. makes for an expensive rev limiter!
Cons:
  • No Better Than A Stock Gm
No, I would not recommend this product.
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rich n
Verified Purchaser
Verified Reviewer
brainerd mn

this is and easy to install rev limiter

August 13, 2015
Good product.
Pros:
  • Easy To Install
Yes, I recommend this product.
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Bryan50
Lee's Summit MO

Great Product

November 09, 2014
I drive 4 mile to & from work, had trouble with fouling plugs on 350 Chevy street car. Put this module in with an HEI Blaster Coil and stabilized spark, no more fouled plugs.
Yes, I recommend this product.
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bakerman11
Verified Purchaser
wichita ks

great product

May 27, 2014
It is a great product especially if you need the plug on the end for dist.
Pros:
  • wiring plug
Yes, I recommend this product.
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DaveO50
Cincinnati, OH, USA

Guarnteed perfomance

May 14, 2014
With the OEM module installed I had a distinct miss over 6000 rpm. after installing this heat module, the miss went away, and in my opinion, the performance of my dirt track car improved slightly. My previous unit lasted me 5 1/2 seasons. Cant go wrong with this unit.
Pros:
  • increase the burn
Yes, I recommend this product.
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DaveO50
Cincinnati, OH, USA

Guarnteed perfomance

May 14, 2014
With the OEM module installed I had a distinct miss over 6000 rpm. after installing this heat module, the miss went away, and in my opinion, the performance of my dirt track car improved slightly. My previous unit lasted me 5 1/2 seasons. Cant go wrong with this unit.
Pros:
  • increase the burn
Yes, I recommend this product.
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Veldon
Verified Purchaser
Roosevelt, UT 84066, USA

Good product wish it was a little cheape

November 18, 2012
I had the old type with the dail and new model is easier to set the rev. limiter. the old type lasted 4 seasons so i will see if the new one lasts any longer.
Yes, I recommend this product.
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Eric
Verified Purchaser
Ironton ohio

Msd

August 24, 2012
Put the module in my dirt track car. Very easy installation of this part, improvement on performance and no need to change limit pills. Can't find one negative thing to say about the module great product
Pros:
  • Easy To Install
  • Improves Performance
  • Provides Accurate Readings
Yes, I recommend this product.
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Page 1 of 1

Product Q&A

2 questions : 2 answers

1 answers

how do you reset the limiter to different settings once its installed

fuzz
April 15, 2015

how do you reset the limiter to different settings once its installed

Answers

April 16, 2015
Eric
Expert
Page 2 of the instructions gives a step by step process for setting the rev-limiter. You can see the instructions here: http://static.speedwaymotors.com/pdf/547-83647.pdf
1 answers

was is the rev limiter on this modual set to is it adjustable and what is the rev limit?

Jman78
April 13, 2015

was is the rev limiter on this modual set to is it adjustable and what is the rev limit?

Answers

April 14, 2015
EricM
This module does have a built in rev limiter. See the instructions in the link below for the procedure to set and check the rev limiter. http://static.speedwaymotors.com/pdf/547-83647.pdf
Page 1 of 1

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