All,

I see some notes here and there re: a single wire HEI conversion and it looks like there are less things to fail. In my life I've been stranded by both a dead coil and dead ignition module, and not at the same time; so this HEI thing looks simple and reliable...

My question is whether a stock or mildly built 360/390 should use a 50K unit or bump it to a hotter model (e.g. 65K, etc.). I'm not racing nor running hotter plugs, but would like to get the most out of the conversion without shortening the engine's life. It looks like I may have to modify or replace my Edelbrock air cleaner(?).

Anyone there with experience making this conversion want to weigh in? For reference, I'm looking at the Assault Racing Products version.

Thanks !
IH -

 

I've done it 2 ways.

1. With the drop-in HEI style distributor. Worked great for many years in my Mustang.

2. With a Duraspark distributor, TFI coil and 4 pin HEI module in the F-250. Cheap and easy.




Either set-up worked very well. In fact we will be reusing #2 in the Foxbody my kids are currently working on.

 

Thanks JP; the one I'm looking at is the drop in (all inclusive, one wire).

 

FWIW, the HEI has a coil and a module too. 30+ years in the garage business, I replaced way more Hei coils and modules than any other kind.

 

I'm using the drop in 1 wire unit in my 351C powered F350. It's brilliant and highly recommended.

I'm running a 14x3 air cleaner with no issues, but did add a 4" riser between the carb and cleaner. It was about 15 bucks off ebay. The stock air cleaner did not fit at all, and I had to modify the thermostat housing to accommodate the larger diameter. It needed a sensor plugged as the sensor stood too tall.

Use a relay to power a fuse box and trigger it with the original distributor wire.

 

For the HEI conversion you'll need to bypass the ballast resistor wire as the HEI unit requires a continuous 12 VDC supply to operate smoothly. The ICM and wiring can go...or taped and tucked off to the side.

Some heat resistant gel swabbed under the unit's module will help reduce internal heat.

 

What "less things to fail" are you referring to?

You *do* realize that the GM HEI has a coil and ignition module that can fail too, RIGHT? The only difference is, GM piled the coil and ignition module on top of the distributor, which causes it's own unique set of problems.

There is absolutely NOTHING to gain by replacing the Ford DuraSpark ignition with the GM HEI.

 

The setup is easy, that's the advantage. Modules can fail but I've had a lot less trouble with modules than with points. If you're super concerned just buy a spare 4 pin module and put it in the glove box. The coil can fail but it's a solid state type, not the old oil filled type unit.

I would run HEI over separated ignition any day.

 

I have done the #2 version and really liked it. I used a TFI coil which is a lot hotter than the old DII. Also put the module on a good heat sink. I much prefer this than opening my hood and seeing that huge fugly wart of an HEI plopped on my engine. I realize the attraction of one wire to those of us intimidated by those pesky electrons.

 

The HEI unit is a bit more compact if you get the kind that's all in the distributor, but as has been said, don't assume that reliability is "perfect". They fail also. Anyone who has any semiconductor controlled ignition should always carry "backup" components. I had a Duraspark II module fail in the AZ desert, but I also had an HEI module fail in N. AL. They are both heat sensitive. Keep them as cool as possible. They won't necessarily give you any warning before failure as will an old style point system. If you need to have some control of the spark advance from the driver's position, use a 5 pin in place of the 4 pin module. I don't know exactly why, but the HEI modules seem to live a bit longer when solid state voltage regulators are used in place of the old point style. Also, as shown, the HEI module does better when fed through a relay and a substantial size wire. Do a lot of research on the two systems. This forum is a good start.

 

The MSD set up is based on the Ford Dura Spark. I myself will stay with the Dura Spark. If anything I would get the wire cable adapter and upgrade to the MSD box.

 

 

Haha, I still run 2 Fords with points, my 59 F250 that gets driven all the time and my 29 roadster pickup hotrod that gets driven in nice weather. I's going on 6 years on the road and I've never touched the points it it. I'm too lazy to mess with stuff that still works

 

I installed an HEI in my dent about two years ago. The primary reason was to clean up the wiring in my engine bay when I was installing my new harness. One wire into the distributor (actually two if you take into account the I wire from the solenoid) and it runs. Granted, I only put about 3000 miles per year on the truck, but the HEI has worked fine. As with any engine ignition component, be prepared and carry extra parts so that downtime is not an emergency.

 

I switched to a drop in HEI from Proform last year after my Duraspark stuff caught fire in my 460.
Three downsides for me where:

1) Distributor is very large and because of the clearance with the water neck (known 460 HEI issue) I only get maybe 5 degrees of adjustment with the vacumn pointed forward. So I pointed the vacumn at 5 o/clock and now have a good 30 degrees of wiggle room.
2) The solid core coil that came with it had fairly thin wires, the wires overheated and started smoking within 30 seconds of initial start up. Replaced it with a Duralast coil from my local parts store. Told them I had a 79 C10 with a big block. I have had 0 issues since then.
3) For some reason my Equus tach stopped working. The needle would just bounce around. (which sounds like a ground issue but it would bounce all the way to 8k...at idle)

Three upsides for me where:

1) Got rid of a LOT of the wires in the engine bay.
2) In my area Chevy parts are much more available and cheaper then ford parts so I can get my hands on them anywhere. Even Walmart has a Chevy coil and module on the shelf.
3) Module and coil take up less space so my spares take up less room in the glove box.

and an extra 4) The automotive groups in my area is heavily into Hondas, mainly Civics and Integras. It blows their mind when I show up in a Ford truck using Chevy, Jeep and Nissan parts to make it run. It was really fun when my throttle cable snapped on the way there, so I had an iPhone charging cable there instead.