I have a 1986 Dodge D150 with the complete stock Electronic Ignition System including the Spark Control Computer and all of the requisite sensors and switches. I have installed a new ESA Dual Pickup electronic distributor (without any vacuum or mechanical advance.) The spark advance is controlled by the Spark Control Computer. I am interested in removing this spark control computer and its sensors and going with a simpler electronic ignition system. Do I just need to get a kit like this one on Ebay: Dodge Mopar Slant 6 Electronic Distributor Kit Fits 170-198-225 Slant Six ? Is there some other distributor kit you would recommend? When I install the new distributor and kit can I then remove the SCC and its associated sensors including the Carburetor Idle Stop Switch and the Vacuum Amplifier Control Unit? Will this improve my truck's performance?

You can do better than that kit for less money, by following the instructions and using the sources described in the HEI upgrade article. Your carburetor may or may not have an appropriate ported-vacuum nipple to correctly operate the distributor's vacuum advance; if not, you will either have to cobble up a workaround as described [url]here[/url], or install a non-SCC carburetor.



Don't remove that -- leave it in place.



That's for your EGR system, not directly associated with the SCC. Whether or not to leave the EGR system intact, and whether and how to modify it, is a separate question from the one you have in mind now.



The truck will run better with a vacuum/mechanical advance distributor and good spark hardware (HEI).

What's the status of this truck's catalytic converter?

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Too many people who were born on third base actually believe they've hit a triple.

Thanks for the reply Dan. However I have a few more questions. I do have a cat on the exhaust system and an EGR valve.

Why not remove the SCC, and sensors including the carb idle stop switch?
(I have the full shop manual and parts manual for the truck.)

I read (and re-read several times) the HEI post and find it very complex and difficult to relate to my particular system. My carb is the stock Holly 1945 with several vacuum ports. I also have a vacuum port for the vacuum line that goes to the SCC vacuum advance control. The timing is set to 16 degrees BTDC.

As I see it, I only need a distributor with a vacuum advance and mechanical weight advance and an electronic control module to eliminate all of the stock spark advance equipment.

Could you provide me with a list of the parts that you recommend for my particular setup to go to an electronic spark control without using the SCC? I would be very appreciative. Thanks.

How old is the cat (meow!)? Is it original to the truck?



Oh, you can -- or at least just take away its job controlling ignition timing.



That idle stop switch makes things better, not worse. Leave it alone and don't get into an unproductive "Rarrr! I'm gonna remove everything that wouldn't have been present on a 1968 model! Grrr!" line of thinking.



It installs the same no matter what you started with...breaker points on a '63 Valiant or a spark control computer on an '85 Ram.



Yes, of course it's got several vacuum nipple. The question is whether any of them (it would be the one presently connected to the SCC) is a ported vacuum nipple -- that is, one that does not have vacuum when the throttle is in curb (hot) idle position.



With an appropriate distributor per the link in the HEI article, you'll want to start out with a setting of perhaps 7° BTDC and tune from there.



That list is in the HEI article.

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Too many people who were born on third base actually believe they've hit a triple.

It is actually far simpler to convert a vehicle originally equipped with a lean-burn system to HEI thanit is to convert a non-lean burn equipped vehicle.

First, on a lean butn vehicle you can completley ignore the portion of the HEI instructions dealing with a ballast resistor. In fact, all you have to do is get a standard electronic ignition distributor, a carburetor that has the correct ported vacum advance, an HEI module, the wiring, and the terminal. A realy is highly recommended, but not absolutely necessary (but still a very good idea).

You can wire it up two ways. First way: wires to the distributor, and use the + and - coil feeds to provide the + and - feeds for the HEI module. Second way, wires to the distributor, use the + coil feed to trigger the relay that powers the HEI module and use the - coil wire for the HEI module.

That's is. Alternatively, you can use the fat black wire that provides + feed to the lean burn computer to power the HEO module or trigger the relay.

It is also highly recommended to upgrade to a E core coil such as those found on Ford products in the late 80s to mid 90s.

Will the Plymouth #3874714 distributor sold by Old Car Parts Northwest work for the HEI conversion on my 1986 D150? The description says it is for 1972-1985 slant six engines. I did not see an O ring on the distributor shaft like is on my dual pickup electronic distributor.

If that distributor has a single elctronic pickup and a vacuum advance then it will work fine. You can transfer the O ring from your stock distributor to the NOS one from OCPNW. You will also have to transfer the distributor hold-down assembly from the old to the new distributor.

Yep that one will work fine, start at 5 BTDC static setting and work up to 8 BTDC when setting the distributor up the first time....

You may need to pull the vacuum advance and replace with a Standard VC-239...if it pings on the highway...

The catalytic converter is about 5 years old. Thanks for the advice on setting the timing.

I am somewhat reluctant to go "Whole Hog" on this HEI conversion since if the truck doesn't start or runs poorly after the complete conversion I will have a number of variables that could be causing the problem.

If I installed a vacuum and mechanical advance distributor from a 1986 Dodge D150 with MANUAL transmission, could I just plug the two distributor wires to one set of the existing distributor wires (run side) in the wiring harness to the distributor and still run the SCC and existing coil? That way I could make sure the distributor was correctly installed before I installed the HEI module and ecoil.

Would the truck start and run with this setup on a temporary basis? Should I leave the initial ignition advance set at 16 degrees?

I have purchased a 1996 Chevy Blazer coil/HEI bracket and an ECHLIN IC29 coil and a TP45 HEI control module as per the diagram in this forum for the HEI conversion. I have found the coil wires and connectors on the Summit Racing and NAPA web sites. I will have to makeup the remaining wires and connectors.

That is equally true no matter what you do.



...you won't get where you're trying to go. Do the job once, do it right, and move on to other things.



Perfect! You're most of the way there!

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Too many people who were born on third base actually believe they've hit a triple.

Okay, I get your drift, but can I use a 1986 Dodge D150 distributor from a manual transmission truck with vacuum and mechanical advance instead of the older distributor I mentioned earlier?

You can, but its advance curves will suck (=you're leaving a lot of performance and economy on the table). Much better to get the older distributor.

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Too many people who were born on third base actually believe they've hit a triple.

Well thanks, that is good to know. I'll get the older distributor and go "Whole Hog"! Luckily, I have three more cars to use when the truck won't start after the conversion!

Converting to HEI on a lean burn vehicle is very easy. In its simplest form it really is just hooking the wires to the distributor and the coil. THe end. You should have no problems.