Proform HEI wiring

Regarding the 225 Buick Oddfire engine in a '68 CJ-5:

The Proform HEI I purchased is pre-wired for what I assume is a GM wiring harness, with a 3-prong flat plug, with orange, black and white wire. The only write up I could find refers only to hooking up one wire to 12v and off you go. The Proform came without any wiring instructions, except that I should plug into the harness. Big help.

Anyone know which wire goes to what, and whether all three are needed to function? The black wire in the center appears to be a ground, verified by continuity check. The orange and white wires go to the two leads on the exciter module, although I don't know which does what. Sort of figured that one might be intended as a tach lead, but I don't really know.

So far I can't get the distributor to fire, and I don't want to cross up the wiring.

Anyone have a connection diagram for this system?

BTW, I know everyone who has tried this says it is the best thing they have done, but for me, this has been a certified biatch to install. I also notice that there is very little leeway in timing rotation available with this distributor because one of the hold-down lugs on the cap is always going to be close to the manifold, so clocking won't change anything. hoping that the timing falls within the available range. If I can get it to fire.

I also noticed in one of the related threads that there are several choices for plug wires. Is there a concensus on the best choice of donor system, or should I make my own?

 

what does your cap look like?

 

I think the plug you are referring to plugs into the cap. There should be a place under your cap near the spark plug wires for three connectors.One of them is for a three prong connector (I think this is the one you are talking about) the other one is for 12V supply from key,and the last is for your tach. They will be labled tach and bat. The three prong connector goes without saying.
I hope this helps Doug

 

Sure enough, the flat plug plugs into the cap. You can tell I haven't seen one of these before. I never would have looked there. That leaves just two other possible connections, one labeled "bat" which should be the switched 12v lead, and one marked "tach" which I don't have as yet. Both those connections hide under the ledge of the cap next to the flat plug, and look as if they take common female ends.

What about the spark plug wires? Any favorite donors?

Thanks to those who responded. I hope it works.

 

I just went and bought a set of hei wires at my local flaps, they all came long, so i cut them to length and then crimped on the connectors that came with them...hth

 

happy to here you figured the wireing out, i tried to get back to you last night but computer experienced a total melt down<ugh> thank god i kept the backup disk! as for the plugwires would get a set for the first year buick went to hei around 1975 they should be the correct length and have the right ends for your setup,unless your driver side manifold <exaust> exits through the front of the vehical like mine did, dont know for sure but that may not be a problem its been 15 years since i fooled with a jeep v6

 

One more thing, seeing you are a little green.
The disttributor needs to be installed unlike any other dist out there. Read this.
http://home.off-road.com/~merls_garage/oddfire.html
Good luck Doug