Quick question re: converting points to stock Chrysler electronic ignition

[barsteel]

Hello!

Tomorrow I'm going to install a stock Chrysler electronic ignition in my Fury. I found several guides as to how to do it, and it seems pretty straightforward (see pic below).

The only question I have is how do I tell which lead from the distributor goes to terminal 4, and which to terminal 5? Are they interchangeable? Both wires coming out of my distributor are black or very dark brown, and one has a white stripe.

Can anyone point me in the right direction?

Thanks...

Chris

 

[BIGBARNEYCARS]

Chris. If you look at the 2 wires coming out of the distributor you will see that the connector corresponds to #4&5 which has the matching 2 plug connector. Piece-ah-cake Man.The instructions will tell you to "WACK" one of those 5 wires 'cuz you don't need it...Follow the instruction and you'll be fine. I've installed those Mopar unitz in /6s and RB engines, Their the best conversions their iz IMHO, Jer

 

[Dobalovr]

100% behind what Jer said. If you have the kit the harness comes with a matching connector for the distributor leads, then 1 lead to the coil 1 lead to run side 12V. The 5th wire is not used. Done many of these as well and it's not as hard as it looks.

 

[stubs300]

You don't say what your working on. Up grade your charging system first if you haven't done so already. READ! charging system overview

 

[CanCritter]

good question...needed a post like this for awhile...was always curious as to how....

 

[barsteel]

Thanks for the replies.

I got the ignition parts when I bought the engine, and the plug for the chrome box did not come with the parts I got. I was able to get the proper chrome box plug from Napa, but the plug for the chrome box does NOT have the plug for the dist on leads 4 and 5. The plug on the distributor has a gray wire and a black wire, while the #4 lead from the ignition box plug is gray, and the #5 is brown with a white stripe.

Based on the schematic, it appears as if the gray #4 wire would match up and the gray wire from the distributor plug. Can anyone confirm or invalidate?

Any idea where I can get the 2 lead distributor plug for the chrome box? I can make it work without the factory plug, but I'd rather have the factory correct parts.

Thanks...

Chris

 

[Big_John]

Go to the trailer section in your local parts store, a replacement plug should be there.

Since you have the plug on the distributor, this should help you.

 

[Mopars & Missiles]

Thanks for the replies.

I got the ignition parts when I bought the engine, and the plug for the chrome box did not come with the parts I got. I was able to get the proper chrome box plug from Napa, but the plug for the chrome box does NOT have the plug for the dist on leads 4 and 5. The plug on the distributor has a gray wire and a black wire, while the #4 lead from the ignition box plug is gray, and the #5 is brown with a white stripe.

Based on the schematic, it appears as if the gray #4 wire would match up and the gray wire from the distributor plug. Can anyone confirm or invalidate?

Any idea where I can get the 2 lead distributor plug for the chrome box? I can make it work without the factory plug, but I'd rather have the factory correct parts.

Thanks...

Chris

Sounds like you need this harness, it has connectors for BOTH the ECU and the distributor. Not pushing this vendor, just an example. The harness is available from many different vendors.


ECU Wiring Harness, Control Unit, For Electronic Ignitions, Hemi

Another source......

https://www.summitracing.com/search...Default&SortOrder=Ascending&autoview=SKU&ar=1

 

[Wildaugust]

When I did mine, my distributor had an orange wire and a black wire. On some dizzies the black wire was replaced/substituted by a brown - white stripe wire and the orange wire was substituted by a grey - black stripe wire. Some, maybe most, boxes had a grey/black stripe wire connected to #4 and a brown/white stripe wire connected to #5. The dizzy will only plug in one way on the stock boxes. The orange from the dizzy connects to grey/black from the box and the black from the dizzy connects to the brown/white from the box. If the connector is missing and you have to splice, you would think that if the chrome box has a grey/black stripe (#4) wire and a brown/white stripe (#5) wire too, that those colors would correspond to the grey/black and brown/white wires from the dizzy, unless somebody was really trying to mess with our minds, LOL!

 

[ItAintJustPaint]

it doesn't really matter which of the wires you connect to the dist, it's just the mag pickup wires, in essence it's a switch that fires the spark, it will work either way

And I'm sure someone will say I'm crazy!

 

[Big_John]

it doesn't really matter which of the wires you connect to the dist, it's just the mag pickup wires, in essence it's a switch that fires the spark, it will work either way

And I'm sure someone will say I'm crazy!

I think you are right that it doesn't matter, but maybe you've over simplified the reasoning.

The reluctor and coil in the distributor generate AC voltage which does turn the power transistor in the ECU on... so yea, it's kind of like a switch, but the real reason would be it's AC voltage generated rather than DC voltage, so polarity shouldn't matter. Switching the power transistor on does charge the primary coil, but switching it off is what makes the field in the coil collapse and makes the secondary voltage.

You probably know all that, otherwise you wouldn't have said it, but I thought I would elaborate.

So... yea, you are correct, although I would keep the wiring as intended just 'cause.

And what the heck, I'll call you crazy.

 

[Deleted member 4847]

Getting the polarity correct when wiring the ecu to the magnetic pickup is important. The car will run with mag pickup polarity reversed, but wont run right.

 

[Big_John]

Getting the polarity correct when wiring the ecu to the magnetic pickup is important. The car will run with mag pickup polarity reversed, but wont run right.

Is that from first hand knowledge?

 

[Deleted member 4847]

Is that from first hand knowledge?

moparts: Mopar electronic ignition double fires at idle

polarity of Magnetic Pickup in distributor. | Moparts Question and Answer | Moparts Forums

I read it in a tech article by Richard Ehrenberg once too, but I cant find the right google keywords to find the article.

 

[Big_John]

moparts: Mopar electronic ignition double fires at idle

polarity of Magnetic Pickup in distributor. | Moparts Question and Answer | Moparts Forums

I read it in a tech article by Richard Ehrenberg once too, but I cant find the right google keywords to find the article.

OK, that all makes some sense. The timing changes because of the polarity.

It probably has to do with the way the wire is wound around the core.

 

[Deleted member 4847]

moparts: Mopar electronic ignition double fires at idle

polarity of Magnetic Pickup in distributor. | Moparts Question and Answer | Moparts Forums

I read it in a tech article by Richard Ehrenberg once too, but I cant find the right google keywords to find the article.

FINALLY found what I remembered reading when I was having ignition troubles. Not written by Ehrenberg but from here at FCBO.

4 pin vs 5 pin ECU wiring....

The "scratch test" is a down and dirty way to make sure polarity between the pickup coil and ECU is correct, and also to test the ignition system in its entirety minus the distributor. If scratch test on male prong makes coil wire spark, but car wont start, problem is in the distributor. Check mag pickup resistance , reluctor gap, top bushing, etc. to find prob. If scratch test makes spark on female prong, fix polarity and retest. If no spark on male or female prong doing scratch test, there is a problem in the coil, ecu, ballast, or wiring.

Its an easy way to narrow down ignition system problems to either distributor or "all the other ****"

Sorry for the long winded reply. It took me forever to find the above post and it was pissing me off.

 

[Big_John]

From the thread:

The reluctor produces what is similar to a cycle of alternating current with one of the current edges being a quick edge and of the right polarity that should trigger the ECU. If the wires are reversed, then then edge polarites are reversed and one of the other edges will have to trigger the ECU but they are 'lazy' edges; some ECU's will respond to these lazy edges and others won't.

This makes sense.. and I think it's explained well in this link in that thread.
Distributor Pickups

Probably still a matter of how it's wound, but there might be something to the shape of the core. We're beyond what I know...

But, I think that really shows that polarity does make a difference.

 

[ItAintJustPaint]

Thank you for explaining it better, i knew basically how it was working, and that it acted like a switch or a pulse to the box, never ran into a problem with the wires being switched or I was lucky. Any problems I had were ground issues.

 

[commando1]

I always felt this modification was as easy and goof proof as any but yet I still learned something new from this thread.