1979 F100 Ranger Lariat 351m

The ignition module is dead. I have in my garage a new Accel coil, Holley 600 carb and Edelbrock Performer 400 intake to go on the engine. I'm also planning a cam/timing chain swap, roller rockers, dual exhaust and eventually higher comp pistons when it needs a rebuild. When I put on the intake/carb I am taking off all the emissions controls as they are not required any longer. I want to go ahead and do the HEI upgrade since the ignition module is $110, HEI is cheaper than that and it will clean up the engine bay.

I read another thread and it ended up with people saying don't do it, just recurve the distributor, or technical talk that was above my pay grade. I am also unfamiliar with the abbreviations for the parts on these engines. I want to make this swap and I am hoping for some help with it.

So, this is what I got from it all. I estimate that about 65% of this is accurate.

1) I need a GM HEI distributor cap. Oh, just any ol' cap will do. No biggie.
2) this will fit on my current Ford OEM distributor
3) I can still recurve the distributor for great justice
4) this eliminates the need for the ignition module (one of my primary goals)
5) I have to jury rig a homebrew heat sink for this (don't look at me, that's what they were doing)
6) I still hook up the vaccuum advance
7) this will run like a sewing machine

So how close am I? If anyone has a model number for the cap I need to buy I would be MOST grateful.

 

Not too close. I'll try to speak to each point, but will surely miss some.

You can't put an HEI cap on a Ford dizzy. Nor a GM dizzy in a Ford engine. What you can do is buy a "one-wire" dizzy for your engine. That's an HEI-style dizzy made for a Ford engine, and in this case a 335 Series engine. That puts all of the electronics in the dizzy and eliminates the need for the DS-II box.

You can recurve that dizzy if you know how and what curve you need. And you should hook your vacuum line to the advance. But you don't need to do anything about a heat sink. However, you will need to do some wiring as the HEI is a power-hungry ignition and pulls a lot of current for a short period of time. So you need at least a #12 wire, and preferably a #10, hooked to a relay that is triggered by the ignition key. And the relay should be connected to the battery side of the solenoid so it isn't using any of the stock wiring.

As for running like a sewing machine, it'll run no better than with a Ford ignition. Both do a very good job of lighting the fire, and there's no such thing as "lighting it better" unless you have a really lean mix, which isn't likely.

 

Thank you, Gary!

 

Also, what is a "dizzy?"

 

Distributor/dizzy

Compression and load can increase the volts required to fire a plug, but a 40,000 volt coil won't provide more spark than a 20,000 volt coil, that is a myth. A hotter ignition and a wider plug gap can improve things some (maybe) but a marginal cap or wires may not handle the higher voltage and can arc to ground.

 

I had trouble getting a HEI dizzy to clear my Edelbrock intake. I actually had to make a spacer ring underneath the distributor and file down the intake manifold runner. That got it to fit but it ended up not working well anyway. I would stick with The Dura-spark setup...

 

HEI dizzys create clearance problems. I tried a Summit Racing setup but it did not fit. There was no way to fit it with my A/C.

I'd stick with OEM Ford and DuraSpark or go with MSD with MSD ignition.

MSD with integrated ignition is JUNK. Don't run MSD without a 6AL ignition box.