chevy style HEI on 318

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Only the people that can put up with that big nasty thing hitting the firewall or wiper motors use those in small block cars. :D

There are sooo many better options that are not so intrusive but are exactly the same function wise.
Here's a few for you to look at.
classichei.com also advance modified and recurved distributors. (Me)
4secondsflat.com (aka FBO) also with rev limiters and advance modified distributors.
"Ready to Run" distributors found on ebay cheap. (Probably the best bang for the budget buck)

What you are asking is about an HEI swap and there is a lot of info around about it.
I myself have the HEI conversion kits that we sell on both our A body Mopars that use the stock electronic Mopar distributors.

Here is one of my kits installed on my own car, but they can be mounted pretty much anywhere.
This uses the factory electronic style distributor and is true HEI.

Removing the old system is a breeze.

DSCF0008.JPG
 
I have one in the 351M in my Ford truck, but TrailBeast is right. There is precious little room in the back of a small block in an Abody.
 
What ignition system do you have right now? If you already have Mopar Electronic Ignition you can easily hook up HEI to your stock Mopar distributor.
If you have points, just get a standard/stock Mopar electronic ignition distributor (2 wire, no lean burn crap) and hook it up. There's lots of how-to articles on this. Modules and e-coils are readily available.

GMHEISchematic.jpg
 
Or this for the 8 pin with weather proof connectors instead of blade style connectors.
There are also others to choose from like below.

8 pin wiring.jpg


HEI_modules.jpg
 
I've read/believe that if you use the 7-pin module (top-right) in our cars, and only connect what's really needed, the 4 pins, the module is in 'bypass'-mode (thinking the engine is starting) all the time.
Think to have read the timing is retarded. This doesn't matter if you set timing normally at the distributor, but I'm wondering if this 'bypass'-mode also have any implications on the dwell time adjustments of the module?
 
Do I understand this correctly?
I'm confused by what I read.
Is the 1.5 resistance necessary to protect the Chrysler ECU or the coil?
This seems to say both things. Perhaps it is both things?
(And the canister coil picture is of a "Flame Thrower". So I assume that coil has 1-1.5 ohms resistance in it.)

Mopar HEI Conversion
Are all electronic ignition systems HEI systems too?
No. The original Chrysler electronic ignition system is not an HEI system. First, it requires a ballast resistor in the primary circuit to decrease the power going through the control module. It was not designed to switch that much power and will fail if you run it without the resistor. Second, it uses a relatively low power coil. The old canister style coil can't put out the kind of power that an HEI system can without overheating the coil.

And.

What is the difference between an HEI coil and a canister style coil?
An HEI coil has very low primary resistance, typically in the range of .3 to .5 ohms. This is the total resistance of the primary circuit and allows a large amount of power to build in the system. A canister style coil requires from 1.0 to 1.5 ohms to survive without overheating. The coil used in HEI systems is a different design, called an E-core because of its shape. This design of coil is inherently more efficient, resulting in less noise (good for computer systems) and less heat. The picture below on the left is a typical canister style coil, and the one on the right is an E-core coil. Both pictures are from www.summitracing.com


Secondly,
FBO Ignition, Distributor tuning and Carburetion Professionals, FBO Ignition systems, Ford Ignition, Mopar Ignition, Ford Distributors, Mopar Distributors, Ford distributor curving, Mopar distributor curving, HEI Ignition, MSD ignition tuning,
shows a picture of a "Flame Thrower" canister style too. Since I've assumed this particular coil has 1-1.5 ohms resistance and this ECU eliminates the ballast resistor does that mean it does something the Chrysler ECU doesn't to prevent overheating?
In other words do ALL canister types have the higher resistance or not.
And if it is the case they all canisters have the 1-1.5, I assume this new ECU prevents the problem of running the ECU with no ballast resistor.
But what about the coil?
Or did the Chrysler original coil simply have less resistance than the "Flame Thrower"?

If I go with the simple four pin, what is a good source for a quality module and coil? Are the products still good or made in China?
No junk yarding.
 
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Here is a pic of my 4-pin HEI setup if it helps you. This is on the passenger fender as you can probably tell. Previously it had Mopar electronic ignition mounted on that fender. I used those existing 2 holes to mount a piece of L bracket. From that L bracket I attached the HEI coil/module bracket. This bracket is shown in that slantsix.org post I linked earlier in this thread. They can be found in lots of cars all over junkyards.

I had to modify mine a little. First the coil had a weird connector. I had to drill-out the studs or rivets (can't remember which) to remove it. I put a normal e-core coil in its place by using 2 long bolts in place of where the studs (or rivets) were.

The module was an 8-pin or something like that. I removed it and put the 4-pin there, it was a direct fit luckily.

Make sure you use thermal grease below the module and make sure it's grounded well (just ground 1 of the 2 module mounting bolts). In fact I need to add an extra ground wire to my module, I cleaned up the wiring recently and I forgot to add a new one!

IMG_20161107_190103.jpg
 
I've read/believe that if you use the 7-pin module (top-right) in our cars, and only connect what's really needed, the 4 pins, the module is in 'bypass'-mode (thinking the engine is starting) all the time.
The megasquirt site has a great explanation. Forget the 7-pin, as it was rare. The 8-pin is best (85-95 GM V-8). You can control the spark timing w/ a Holley Commander 950 and other engine controllers. If you leave that plug off, it simply doesn't adjust timing from the pickup pulses, i.e. pulses the same as an old Mopar ECU would (but stronger spark).
 
lotta hate for the gm style dizzy but lots of love for useing the parts out of it,...its a dang good dizzy and tooooo easy to wire up....just one switched on hot wire to right plug of the only 2 plugs on the cap other than the plug wires,..the other plug is for your tach! that simple,..yes its big but being big keeps the spark splater inside the cap in check better at higher rpm with this dizzy is good to well past 7,000 rpms! itll be a tight fit ol chevy boys had to hammer there fire walls in them novas and camaros to up grade from points too no big deal just dont go rambo on it plan it! dizzy just like it spins 7800 rpms 35 laps on a dirt limited sportsman car i got going on 5 years think ive put a new cap and buttun on it once! can open up your plug gaps to 45-48 and lite the fires just fine!
 
lotta hate for the gm style dizzy but lots of love for useing the parts out of it,...its a dang good dizzy and tooooo easy to wire up....just one switched on hot wire to right plug of the only 2 plugs on the cap other than the plug wires,..the other plug is for your tach! that simple,..yes its big but being big keeps the spark splater inside the cap in check better at higher rpm with this dizzy is good to well past 7,000 rpms! itll be a tight fit ol chevy boys had to hammer there fire walls in them novas and camaros to up grade from points too no big deal just dont go rambo on it plan it! dizzy just like it spins 7800 rpms 35 laps on a dirt limited sportsman car i got going on 5 years think ive put a new cap and buttun on it once! can open up your plug gaps to 45-48 and lite the fires just fine!


Reviving an old thread lol but which hei dizzy did you use?
 
I am no fan of E-core coils on non-CDI systems.They are built for 500 or more volts input and because of that, don't seem to do well on just 7 or 8
The first question is what do you want to upgrade from, and the second is like it; why.
But if your engine actually needs something hotter, I highly recommend the Accell SuperCoil sq top P4120889 and it's associated 1.0ohm resistor P5206436, in my catalog. Put it on a relay, and I think you could weld with that thing. Mine has been absolutely trouble-free since ~2002; from 650 idle to 7200redline. I put mine up on the apron, horizontally, connections down, with a 30" hi-tension lead. Watch out! it does get hot.
I use the factory trigger in a 1973 distributor, that is on it's third or fourth engine. The trigger was replaced in about 2004, with another used one. The amp I use is built in to a Jacobs; dash-mounted,dial-back, electronic, timing delay box; that I installed in about 2004. The box also has a dial-type adjustable rev limiter.It works great as a cruise control; If I get to speeding, it starts messing with the sparks and wakes me up; very handy on long trips. Yes I really drive my 400+ hp 367/68 Barracuda on cross-country trips. She gets around.
 
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