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GM Module in Lucas box [ was PICKUP COIL + wire?]

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I'm dumping the Lucas module on my '79 and converting to a GM HEI 4 pin module and I need to know which wire is + and which is neg on the PICKUP COIL in the dizzy. I can't find any information anywhere. That's all I need to know and could have it running again as early as tommorrow morning (schedule permitting) once I have this information.

I tried figuring it out w/ my meter but I get the same voltage measurements either way when it's spun.

Anyone know for sure?
 
Re: Anyone know which wire is + on the PICKUP COIL?

So.......I set out to see if I can figure this out on my own. While investigating, I decide to pull the box and see if anything inside is burnt or maybe find out which wire is which. I open up the box only to find........... A GM 4 PIN MODULE !!!!!!

Apparently, the $329 Lucas replacement is nothing more than a $15 GM Module in a box with a Lucas # on it.

Surely I can't be the first to discover this, right??????
 
Re: Anyone know which wire is + on the PICKUP COIL?

From here (Spitfire site)

https://www.triumphspitfire.com/substitute.html

standard 4-pin GM Ignition Module
part number TP45SB for 1980 Chev. Chevette w/1.6 L engine.

I've seen it on the web but never really seen it discussed here - good for you!!
 
Re: Anyone know which wire is + on the PICKUP COIL?

I knew there was no way that it went unoticed for 30 years. This is gonna make life so much easier. I can't tell you how many of those 4 pins I use to have laying around. I have since thrown them all away. Now I don't have to fab up anything up and can just put it right in !!!!

I had no idea this was so. Maybe most folks here don't know about this? I think I'll change the thread title. I'd hate to see someone spend more $$$ then they have to on ignition stuff to get going again. Worse yet, I'd hate to see someone have to WAIT on parts to get going again.
 
Re: Anyone know which wire is + on the PICKUP COIL?

I have heard that the later Lucas CEI system was actually the GM ignition module in disguise. The older OPUS system from '75-'77(?) was a different animal that was notoriously unreliable and was replaced with the CEI setup. I don't know exactly when the CEI was made standard on the 1500s, but my '77 was blessed (cursed?) with it.
 
Re: Anyone know which wire is + on the PICKUP COIL?

It's in there all right. I put the new one in, installed a MSD Blaster 2 coil and the beat-to-fit, paint-to-match Accel Super Stock V8 wire kit and it run great now..........and I have enough wires left over to make another set. These have the tinned copper wire core but still allow for zero radio noise. For $20 I'm happy with the wires (for now).

One of the bad wires had almost 60K ohms per foot !!!!


It now has a hot spark with a nice "CRACK" when it arcs. it was really weak before.

I really don't need more, but I do have an MSD 6AL and a GM MSD dizzy module, so since a have a GM module set up already, I might get stupid with it later but it runs good now. My hard start problem is now gone.


I love pulling a wire and hearing that nice " CRACK CRACK CRACK ".

I can't stand weak spark.

Seeing that it has a HEI module in it, I'm tempted to run straight 12v to it and heat up the spark alittle more. My only concern is the pickup.

I don't mind frying it. It's the only thing I haven't changed yet and probably should be replaced. It would be a good experiment.
 
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