I have no experience w/that coil, sorry. The concern I’d have w/using any non-oem coil is if the primary resistance is too low, b/c that could put enough of a load on the electronic ignition system which might cause its circuit to overheat and fail. There’s other factors to worry about too w/using a non-oem, but over-current would be my main one. Resistance can vary from coil to coil & with ambient conditions.
The shop manual does not give any information about the specific flavor of the two coils it makes reference to, other than the primary and secondary resistances. I would think that would be a reasonable way to shop for a replacement. The Accel 8140 is well within the specs in the shop manual. Mopar no longer has this coil for sale.
The carb is in very good condition, all gaskets are sound and all parts are clean and tight. I have a vacuum gauge in the cab reading manifold vaccuum, and it is very strong. I am beginning to zero in on the coil as the weakest link. I mention the reasons in this thread in a back and forth with George further below.
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The plugs are very healthy looking, no oil, no soot, just toasty tan ceramic insulators, and clean everywhere.
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Just HC, everything else is good. This is leading me to try to get the best, hottest spark I can get.
Your faith in the effectiveness of the political system is heart-warming 
What are your typical HC test readings vs the passing level?
On my Corolla, the test is done at two speeds while the tech drives my poor Corolla on a roller-treadmill. My typical readings (max) were in the 120’s, passing limit is 130. PPM presumable units.
Once I figured out the air filter component, readings dropped to 50-70.
An 87 probably has a pretty complicated electronic controlled carb. Probably uses a PCM and o2 sensor feedback to adjust the carb’s mixture. Do you have the necessary specs and carb testing & service procedures?
The weak point on the original 6280 Holley carb is the mixture control solenoid, which is no longer available as a replacement part. In fact, it was no longer available when the one on the original carb went south at 60,000 miles. Someone had bought up all he could and was selling them dearly on eBay. After going through 7 or 8 kinds of hell with the 6280 I swapped it out for a modified Holley 2280, same body but without the mixture control solenoid. I was passing with it with no problems until the State ratcheted up the point at which the truck failed. That happened twice. Now it is always a struggle.
Any way a speed shop with a dyno and exhaust analyzer could re-jet/adjust your 2280 to meet CA specs?
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Re the copper cap and rotor contacts I long ago noticed that the quality parts had much closer gaps.
I managed to do that already at the local mom n pop smog shop on their dyno. I think my best bet at this point is to get my hands on a coil that is within factory specs for the primary and secondary resistance, which is 1.34 to 1.55 ohms on the primary, and 9,000 to 12,200 ohms on the secondary. The one I have on the truck now is 1.7 on the primary and 6,960 of the secondary. Some chain autoparts store sold it as a replacement for the original on this truck. It works to run the engine, but I can’t help but think that a longer, stronger and hotter spark will give better combustion. The Accel 8140 specs at 1.4 primary and 9,200 secondary. I don’t know if there is any other factor to consider in a coil other than primary and secondary resistance.
If the mom and pop shop has a scope use it to judge your ignition performance
The last carb I had was on my 74 olds that I remember. It had a shut off solenoid to close the throttle down more to stop the dieseling because it was leaned out so bad from the factory if that’s what you meant. So they leaned it out and then kicked the throttle up so it would still idle, and then put plastic caps on the jets so you couldn’t mess with the mixture. Breaking the caps off allowed going back to a normal mixture and idle setting. No testing in Minnesota so suppose breaking the caps off would result in a big fail. So I suppose you could lean it way out and advance the throttle so it would run, then put it back after passing. But why are you still in California?
I love the clean ocean breeze, warm year round weather, beautiful scenery. Tell me about Minnesota winters.
That is the reason he buys a new car every ten years, the snow up to his neck is a bonus. 78 degrees in Nevada today.
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Me neither. I hope a new coil helps, but it may not. If there are options regarding oil viscosity, I’d use the higher-viscosity oil (like 10w-40 if both 10w-30 and 10w-40 are allowed).
Which part of the test does it fail, exactly?
Failed on HC. Passes on NOx and CO.
But was it HC at idle, or under load? Not sure what they test.
After exhaustive searching and checking specs and prices, I ordered a PerTronix 40011 Flame-Thrower Coil for $35, plus tax, free delivery, from Amazon.
I bought the following items at RockAuto:
Standard Motor Products 7656 wires
Wells Vehicle Electronics 3D1069A Cap and Rotor with brass contacts
I am hoping this will generate a hotter, longer spark for more complete combustion. When checking the spark against ground in the past with cheap aftermarket coils it has always looked weak. By that I mean it was dim orange colored instead of bright white or blue. I should know in a week or two if it makes a difference.
Ha Ha, you’re funny. Maybe if you pour bleach in the gas that will help.
The spark (when visually checking using a spark plug) definitely shouldn’t appear orange at all. As you say, it should appear white or bluish-white. If you are seeing orange, it could be the coil, but it could also be the ignition electronics, or the wiring or grounding between the two. My truck won’t even start if the spark is orange- or red- colored; usual cause in my truck’s case is the points surfaces are pitted or corroded.
A poster here from yesteryear had quite a bit expertise on this subject. In his case it was Subaru carbs. He has since passed away, but I still run across his informative & helpful comments here from time to time. You can probably find his carburetor related posts using the forum search feature, link above right, search by poster’s handle. I think his Car Talk handle was @ok4450 . As I recall he mentioned the mixture solenoid as being a common problem on the Subaru carb too. You definitely want the mixture control solenoid & linkages to move freely.
Just curious, how do the emissions folks decide if the owner of an older vehicle is allowed to replace an unavailable carb w/a different part? Did you need to get their approval?
One coil design requirement is that when properly mounted it will dissipate the heat caused by the sparking faster than the heat is produced, and will be able to handle the resulting temperature. Your emissions testing shop probably does the testing w/the hood open, which will help prevent the coil from overheating during the test. Coil-overheating is one reason to use a coil spec’d for your truck. An overheated coil will fail sooner and need replacement, and if severely overheated, could cause an engine fire. Pertronix ignition products seem to get pretty good reviews in car-magazines.