Coil on Plug Using Standard HEI Coils, Design Thoughts?
 

Ok, so I'm wondering what the best method would be to fire my spark plugs directly from my coils, without the use of ignition cables.

I've came up with three idea's thus far.

1. Mount the coils in a way that smashes the output terminal into the spark plugs like below.
Attachment 653564

2. Do the same as above, but with the addition of a collar with two set screws, therefore you would be able to lock the two items together.


Or,
3. Drill and tap the outputs of the coils. That way one could simply screw the coils onto the tips of the spark plugs. The only problem I see with this, is the diameter of the output post is .205" the smallest sections, and the spark plug cable stud is .150" thick, which seems to be a little weaker than I'd like. I'd really like to use this idea, just unsure if .0275" is a thick enough wall not to crack.
Attachment 653565



Then,
I would need some sort of insulation. The only idea I have is to cut a straight spark plug cable end off of a spark plug cable and use that piece over the connection of the coil and plug.

Or,
Is all of this a bad idea?

Thoughts please.

You'll need some form of strain relief between the coil and plug. Vibration and thermal expansion will ensure a failure of one or both components otherwise.

Not sure which chassis you're working with, but I know those coils won't mount as a COP in the 3rd gen chassis without the coil being mounted at at angle to the plug. Not enough clearance to the frame rail.

Ya, definitely needs some sort of strain relief. I was imagining bolting them to block so hard that they would just stay put, but your comment sheds a lot of insight.

And this is for a second gen, with all the accessories stripped. I'm pretty sure I have ample space.

I actually really just want some sort of .5-2 inch long spark plug cable. Similar to factory Coil On Plug connection designs. But, I can't find any made at that length. And really avoiding wires altogether would be nice, for longevity sake.

Magnecor has a custom wire program, and 5 inches long with 90 degree bends on both ends is the shortest configuration they offer. They do offer a 6 inch long model with two straights. (from spark tip to coil tip)

They do fit well, except the rear rotor leading, it only has a little over an inch of clearance before the coil hits the steering rod. So I wouldn't be able to use anything straight over a half inch or so long...