HEI... here we go...

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theFightingFew

Always Learning/1975 Valiant Custom/1974 Valiant
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Well I finally squirrelled together the last of the components to do me up the HEI conversion... Just gotta run and get some electrical connectors and away we go.
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Good luck. Post up the details. One of the hei modules has a 7-10 degree starter assist retard on one of the extra wires.
 
Can you post what parts you are using as I want to upgrade the ignition on my daughter 63 valiant wagon....
 
Ok well I was hoping to have it in the car tonight and be zip'n down some twisty country backroads... my wife always says I get a bit over ambitious... but here is the progress...
To be clear I am pretty much following the recipe posted by @slantsixdan over here - HEI Electronic Ignition Retrofit How-To

PARTS I AM USING: (because @70aarcuda requested )
Heat Sink - AMZN LINK
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Bracket - AMZN LINK
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Coil - AMZN LINK
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Control Module - AMZN LINK
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Pigtail - AMZN LINK
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Heat Sink Goo - AMZN LINK
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Lightning Cable - AMZN LINK
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Electrical disconnects, wires, and some #8-32 x 1in machine bolts/nuts from the hardware store.
 
What plug wires are you using?
 
If i was more knowledgable I probably would have sourced different parts (maybe) but I was easily able to modify what I had with a Dremel cut-off wheel and some drilling.

The heat sink lined up with the bracket
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The control module was out of position due to the first fin on the heat sink - see how the holes don't line up
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I removed the first fin with a Dremel cut-off wheel
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All lined up
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But the control module had some feet... so back to the Dremel and off they came
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The coil only lined up with one bolt hole so I inserted the one bolt and snugged it down then marked a new hole through the back and drilled
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Yay...
 
Threw some heat sink goop on the sink placed the control unit on and bolted down...
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Added connectors to the pigtail and made up some wire for the distributor...
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and this is as far as I got for tonight... booooooo... tomorrow's another day...
 
What plug wires are you using?
Hey Rusty, I have a set of those extra fancy LiveWires I harvested from my '74 Valiant that the previous owner put on... and took these guys off the '75 that I'm doing this conversion on that I've been running since I acquired the car... I'm putting these in my original parts storage box... I like the way they look!
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Is the distributor a stock mopar /6 unit?
Yes - original unit that came with the engine/car (though I do not know if it is the original one "from" the car - I don't know how to read codes yet) - this is from when i took it out last year after acquiring the car to clean it up a bit, check the reluctor gap and drop some oil on the felt... it still seems to be functioning well
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UPDATE:
So I got a bit more done last night. I need to do clean up but I wanted to test it to make sure I had an understanding of what I was doing... I'm sure there may be some placebo effect going on but it feels stronger and much smoother...

I removed the Mopar 5 wire ECU and sealed up the connection - I'm really not sure what to do with it... I wouldn't mind going through the harness and cleaning up un-needed wires but I also feel I should leave it as a fall-back to go back to original set up if needed... any constructive thoughts are appreciated.
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I created 10 gauge jumpers for the ballast resistor - I got this idea from a B-Bodies only post here. I thought it was a good way, again, as a fall-back.
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I removed my Accel Super Stock coil, bracket, and I assume the cylinder-ma-bobber is some sort of noise canceller (I'm interested in knowing more if incorrect)?
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I sealed up the coil wires and the male/female torpedo connector - Again, I'm not sure what to do with them... would love to clean up - constructive thoughts welcomed!
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So here is the install of the coil and control module.
  1. I ran a ground from the control module to the alternator.
  2. I am currently picking power up from the 12v ignition switched BLUE WIRE coming off the alternator. This previously went to the electric thermostat choke pull-off on the original 1bbl Holley 1945 set up which has been replaced with a Holley 350 cfm set up with electric choke also powered by the blue lead.
  3. I currently don't have a relay set up for the coil as I was just testing - THIS IS WHERE I COULD USE SOME ADVICE as I'm getting a bit lost at that point in the recipe linked above.
    • If I run a 10ga. lead from battery + to a relay controlled by the BLUE LEAD would that be CORRECT? Do I even need a relay if i'm using the blue lead? (The blue lead is also feeding an aftermarket volt gauge.)
  4. I still need a fuse. I imagine this would go on the 10ga from the battery +? (or between the blue lead/coil if no relay as above?)
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I'm not 100% content with the location of the install but am currently limited by the length of the coil wire. I have read various opinions about coil wire length... shorted is better etc... but i'd love to move this whole thing back towards/to the firewall - Thoughts? All in all it's definitely not the sexiest package, but like everything else when working on our cars I'm proud to be going through the process of building it out myself.

Thanks FABO
 
You can make it "cool" looking if you use your imagination. I built this and mounted it to the right front side of the engine.
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I should send you a gold Pentastar to stick on that big glaring "GM"! Nice work.

Here is the GM 5 pin HEI hack: "5 pin HEI module out of an '80 Oldsmobile Toronado w/ 307 or 350 engine, works just like a "regular" 4 pin HEI module, but ground the 5th pin and it will retard crank timing 5 degrees" Another states 5 pin HEI "Used on early non-efi HEI vehicles for detonation control such as 1980 Pontiac TransAm Turbo (301 olds), retards BY 10 deg when 5th pin is grounded" eg. Standard Motor Products #LX-330 (?)
 
would the Hei module have worked better if you flipped it over ? So the connectors are pointing toward the coil.
 
Did you see this?
Yes - maybe not that one specifically but... In any case I read/saw somewhere that some control modules emit different frequencies/wavelength (or some other kind of magic) so I was reluctant getting the whole package just to have to swap out the control module anyway. Since this way my first HEI install I opted to follow the recipe @slantsixdan posted over on slantsix.org with the parts he mentioned as I felt it was a safe and thoroughly researched path forward.

Plus, making the thing out of all the parts was fun, and though I had to do some minor modifications I enjoyed the problem-solving/building process... it gave me something to do instead of sit'n in front of the TV at night :)
 
would the Hei module have worked better
"worked better" or "fit" better? Worked - no as long as wiring was correct it would be the same. Fit - no it still would have hit the fin and if i remember correctly was more misaligned due to the inside corners of the module being at a further distance from the mounting holes.
 
I should send you a gold Pentastar to stick on that big glaring "GM"! Nice work.

Here is the GM 5 pin HEI hack: "5 pin HEI module out of an '80 Oldsmobile Toronado w/ 307 or 350 engine, works just like a "regular" 4 pin HEI module, but ground the 5th pin and it will retard crank timing 5 degrees" Another states 5 pin HEI "Used on early non-efi HEI vehicles for detonation control such as 1980 Pontiac TransAm Turbo (301 olds), retards BY 10 deg when 5th pin is grounded" eg. Standard Motor Products #LX-330 (?)

Standard LX330 is the '80 Toronado application, LX331 is for the '80 turbo Trans Am with Canadian emissions (US applications used a 7 pin module). There are no details listed about the difference in retard degrees if any.
 
^^ the LX-330 was referencing the 307/350 Olds engine, my cut and paste put the T/A reference in between, causing 'confusion and delay' (poor form pishta!) :BangHead:

Update>> @nitro_rat they look to both retard 10 degrees, one lists 5 crank timing , other source listed 10 timing (probably @ cam)

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I should send you a gold Pentastar to stick on that big glaring "GM"! Nice work.
Ha! I know... Everytime I look at it I get a twinge of pain... Like when you have a small metal filing stuck in your finger you just can't seem to it dig out but you know it's there.

I'm definitely going to have to dress it up. And I appreciate the compliment.
 
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