HEI old school distributor

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I8NEMO

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Im looking for recommendations on a distributor for my 340. Are there any HEI units that mimic stock? Also I'll be firing this motor soon, car is a shell save motor and running gear, no wiring harness or dash in car. I'll have a mechanical oil pressure gauge and temp gauge rigged, what are my electrical dos and don'ts without using the wiring harness? Ive spun new motor oil pumps with a drill in the past, what are some break in rpms and run times ? Guess I should rig a tach for sure yes?

Thanks
 
The way to do that is to use a Mopar breakerless dist as used in the early 70's and later, and use it to fire an HEI module. You can use the stock coil or not, and eliminate the ballast resistor. There are hundreds of posts on this subject, a few guys have even gutted a Mopar box and installed a GM module inside

Search:

67dart273, hei - Google Search

A nice diagram done by a member here for a 4 pin. Pay attention to the pickup coil wiring polarity. You must break/ file a locator "tit" off the bottom of the module, mount it "flat" on an aluminum heat sink, and make sure the mounting holes are GROUNDED

4pin-jpg.jpg
 
Pardon my ignorance but what makes the GM ignition module so desirable
 
Pardon my ignorance but what makes the GM ignition module so desirable
As above, "for now" and likely because they are more popular, are better QC than the Mopar copies. Also they don't draw current if the key is on/ engine stopped. Also if a proper coil is used they make more spark. Actually they make more spark even if used on a stock Mopar coil LOL
 
This may not be what you are looking for, but Davis Unified Ignition sells a Mopar unit that looks mostly stock. I ran one of their other style units on a Ford back in the day, and it was great . The plus is you give them your engine specs, and dial the curve in for you. They however are not cheap.

https://performancedistributors.com/product/dodge-tri-power-distributors/
 
Thanks! I was just reading about this very set up, I like the old school look for sure. DUIs larger unit looks pretty simple with only one wire connection but pretty sure it will not fit due to firewall proximity.
 
The GM 8-pin module shown in post 3 is best (1985-95 trucks). Also grab the GM coil and the wire which connects the 2 and the 2-pin connector w/ wire to the GM pickup. Cut the GM red (+12 V) and white (tach) wires as long as you can. It is better because the connectors are weather-sealed and the cable takes care of the coil wiring. Some engine controllers can also control the spark timing of it (ex. Holley Commander 950 & later).

The Mopar distributor pickup will trigger the HEI, but you need the polarity correct. I have the colors documented somewhere, but regardless you need to verify w/ a timing light. Connect the coil output thru a spark plug (or simulator, or just a gap). With distributor cap off, spin the distributor by hand or crank over the engine (won't fire) and verify that when the timing lamp flashes, the pickup fingers are aligned. If not, switch the pickup polarity.
 
The way to do that is to use a Mopar breakerless dist as used in the early 70's and later, and use it to fire an HEI module. You can use the stock coil or not, and eliminate the ballast resistor. There are hundreds of posts on this subject, a few guys have even gutted a Mopar box and installed a GM module inside

Search:

67dart273, hei - Google Search

A nice diagram done by a member here for a 4 pin. Pay attention to the pickup coil wiring polarity. You must break/ file a locator "tit" off the bottom of the module, mount it "flat" on an aluminum heat sink, and make sure the mounting holes are GROUNDED

View attachment 1715592256
Quick question: Does the coil last taking the full 12-14 volts consistently?
 
Quick question: Does the coil last taking the full 12-14 volts consistently?
I think they were designed for full voltage. GM HEI didn't use a ballast resistor. Another good reason why the GM modules are good. 12v. baby!
 
I think they were designed for full voltage. GM HEI didn't use a ballast resistor. Another good reason why the GM modules are good. 12v. baby!
so then the stock mopar coil shouldn't be used?
 
I used a stock coil with a 4 pin HEI mostly as an experiment. It has held up, and gives a hotter spark than stock. I did the same deal with a (follow this!!!) old Cletrac crawler swapped Toyota 20R with stock Toy breakerless distro, GM module, and stock coil. No idea where it is now, I sold it

......and I forgot........Massey Fergesun sheet metal LOL

_mg_6370cs-jpg.jpg
 
Good question. What does everybody use?
An e-core coil is better than the stock coil, though I can't say exactly why. The stock coil could spark internally or perhaps it has different inductance to give a lower energy spark. The reason the 8-pin HEI module is better is that you can easily pair it with the GM coil, using their factory cable. If for some reason, you want to stay Mopar, you could use the e-core coil from a Magnum engine, but would have to fab your own cable (junkyard to get the mating connector too). It is mounted on the front bracket in Magnum engines.
 
Im looking for recommendations on a distributor for my 340. Are there any HEI units that mimic stock? Also I'll be firing this motor soon, car is a shell save motor and running gear, no wiring harness or dash in car. I'll have a mechanical oil pressure gauge and temp gauge rigged, what are my electrical dos and don'ts without using the wiring harness? Ive spun new motor oil pumps with a drill in the past, what are some break in rpms and run times ? Guess I should rig a tach for sure yes?

Thanks

Mopar HEI Conversion
 
Why not use the stock Mopar electronic ignition?
 
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