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What 4 pin HEI module you you all use?>

21K views 18 replies 9 participants last post by  Dave Ray  
#1 ·
Summit has the usual suspects, Accel, Pertronix, etc. THis is to replace a module in a harness Dave Ray made, just in case the MSD craps out using his mag trigger distrib.

Any preferences?
 
#2 ·
#4 ·
I keep a Napa Echlin in the glove box in case my MSD module fails but it never has. I would use the Echlin if it weren't for the built-in rev limiter on the MSD. Remote mount the coil and you may never kill a module.

I've never noticed a performance difference between different brands.
 
#6 ·
NOT AN AD, just info. When Gene and I built his MSD Trigger only conversion, I also built him a stand alone totally remote HEI setup, with HEI module and input/output/ground wires, with alligator clips on their ends. This allowed Gene to use a real world timing light, and no dial back when he wanted to set, alter the timing in the system, then go back to the MSD when he was done with it.

For me, serviceability is essential, the more versatility, the better.

Later on, it donned in my ancheint, old fart backfire head that this setup could be made as a stand alone setup for any of my MSD Trigger Only conversions, if someone wanted to go back, to an HEI from an MSD, simple. There is a picture of what I came up with on the website, but that one doesn't have the alligator clips to temporarily attach it.

As far as any HEI COIL, I am a firm believer, from decades of hands on experiences, that the remote mounted, oil filled round coils are the best to use. From way too many HEI module failures with the epoxy coils in the caps gong bad, slowly causing both their, and module failures, I use the oil filled coils, and the module failure issues virtually stopping when the in cap epoxy coils are changed out. I have a 1986 GMC Safari with 4.3 V6 and factory 5 speed. It used to take an EFI HEI module and coil out every year, just stops dead on the road. In 2010, I had a module and coil fail, and replaced the EFI-HEI module with the same standard one I had always used, and the coil with one of them I use, oil filled round, for my small-body conversions. This van is used for a senior citizen's food program, it carries the canopies, tables, facilities for distribution, is my pickup truck, and goes about 30K per year, and it hasn't farted, belched, hiccuped in all these last almost 10 years. It even gets better fuel mileage than the old epoxy coil did.
 
#10 ·
#9 ·
Mmmmm.....$55.00 for a decal, let me run right out and squander that money.

Rich, both Mallory (now owned by MSD/Holley), and MSD made coil covers that moved the coil out of the cap on the large cap HEI. Past that, one had to run the two wires, power in BATT, and signal TACH from the side of the cap to the new remote mounted coil, and a coil wire, which most better parts stores carry pre-made sections of coil wires that will work with the kit. I don't remember ever seeing a coil wire supplied with either kit.
 
#11 ·
I have an old msd wiring diagram from a magazine.
Second picture is of a setup I did with msd distributor and HEI module in the link in my post above. It was not finished in the picture.
Last picture is a setup I have in the trunk of my msd box fails, will just take a couple of minutes to hook up.
 

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#12 ·
Dave, I ought have shown the folks what I was referring to. Marcus, that's pretty impressive sir! I wouldnt have figured it out w/o Dave's expert assistance. Dave's harness is pictured. I was going to dig Dave's instruction set up, but now I dont have to. THNX MARCUS! It is pretty simple, two wires to the mag trigger, two to the coil,and one hot lead to bat.

I asked Dave to build me something that provides a fail safe for the MSD box when he built me a mag trigger distributor. ( now installed on the Mark Jones 467. ) Geez, I've had this since, what Dave 2002-2004?

I used it once Dave in 2015, when the MSD failed. The HEI holder got wicked hot, put a nice 2nd drg degree burn on my hand, and then it failed. I **ASSUME* it was due to a bad ground. ?? Anyway, there is a fat ground strap back there now, so that should not be an issue. But I want to replace the module before it goes into the travel kit. PS, ought I use dielectric grease between the module and the jig you built?

I'll say this about the MSD/Dave Ray ignition system, it fires up within one rev, meaning almost immediately. This engine does not crank, it just FIRES!

Thank you all for the replies.
 

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#15 ·
Techs are usually accommodating to those that ask questions, to bolster sales of whatever they have to pawn off on people. In a GM point distributor, function is EXACTLY the same no matter if the distributor body is cast iron, aluminum, bubble gum, or silly putty.

Gene, yes, grounding is critical for the HEI modules, and a bad, dirty, corroded ground will allow heat buildup from increased ground resistances. Yes, di-electric grease under the module works, I go a bi farther, I use the special heat leaching compounds for under computer parts, seems to transfer heat better than the stuff that comes with a new modlue. Just my preference.

I see no difference in the Crane/FAST coils over the oil filled PerTronix (the epoxy PerTronix is pure junk, though), nor other extremely good stock OEM oil filled round coils available.

Although the coil changeover shown is good, I build my own coil transfer devices for the tops of the large HEI's I get conned into working on. Mallory and MSD both made virtually the same kit as shown, great quality, works well, but, I don't like the way the wire terminal to button spring bar is set up, nothing to keep it firmly in its curvature and place, except its own metal strength. Just my preference. Main thing is to get that epoxy coil out of the cap.

Keep it up, guys, you got this nailed down right.
 
#17 ·
Gene, let it go, please. There are some here that just will not stop, and accept that some people have been doing this disruption for decades.

Take, for example that I was one of the people that worked on developing the GM large HEI. We had the modules worked out by 1974, the same time Ford introduced, and was installing their their new Dura-Spark ignition. So, one of the things I did was go buy one of the magnetic pickups from a Ford dealer, and see if it would run an HEI module, late 1975. It worked well, and is the basis for the conversions I do. So, MSD comes along and invents it, in 1980. Do I care? NO, I just want it to work right, let someone else take the credit. I never did like the pickup coils in the large HEI, nor the in cap coils, either.

Since both the GM cast iron, and aluminum points distributors use the same points, condenser, vacuum advance type, rotor and cap, the same must be true of the other GM points distributors of the Era, "I've had a few distributor techs tell me the stock iron distributor triggering a CD box is the way to go..". Same can be said of any manufacturer's points distributors, car makers, after market distributor makers, and even MSD, but, then, they did elect to use the same magnetic pickup I chose way back in 1975.

I'll just got forth and do what I do, and let everybody else speculate, bloviate and set the history as only they see fit. It ain't worth wasting time on defending any of it.
 
#18 ·
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