Hollowing out the cat may or may not affect the smog readings, depending on how the truck is running. If the engine is in a good state of tune, the hollowing out the catalytic converter will definitely make the truck pollute more.

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Casually looking for a Clifford hyperpak intake for cheap.

Yes, the '86s all had Lean Burn (though by then it was mostly not called Lean Burn any more). Some of them had feedback carburetion with an O2 sensor installed in the rear wall of the exhaust manifold's central collector (facing the firewall); some did not. High-altitude and California vehicles mostly do have the O2 sensor and feedback carburetion.

Feedback carburetion gets along a LOT better with a catalytic converter than non-feedback carburetion (though fuel injection's better still). If, as is likely the case, this vehicle must pass emission tests of any kind, then probably the best way forward is to keep the feedback carburetion but use a feedback 2bbl rather than the original (tiny) feedback 1bbl. These can be had off '81-'84 318 passenger cars; I have one brand new (not "remanufactured") such carburetor on the shelf for whoever wants to buy it for such a conversion. You don't need to allow the computer to control the spark advance if you don't want to; you can install an ordinary mechanical/vaccum advancing distributor if you prefer. Though if I were in possession of such a truck as this, I would be very strongly tempted to try the feedback 2bbl swap with the computer controlling the spark advance first. Either way, if you disable the EGR be sure to keep your ears open for pinging. You may wind up keeping the EGR, though you might want to update to a transducer-style EGR valve for better, more refined control of EGR flow in accord with engine running conditions.

Catalytic converter(s), see here and here. Good ones don't restrict the exhaust, and having one's a good idea for the same reason we also plumb our houses so the toilets go into a treatment plant instead of just flushing out into the street, river, or lake.

Exhaust system/muffler selection, see here.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

This is great info. My 1945 holley doesn't have any feedback and the only electronics is the idle stop soleniod and there also isn't an O2 sensor. I believe the P/O bought this truck in Montana as he lived there at the time so thats probably why this one doesn't have the feedback and O2.

I'm going to sit down and see what parts I need and what I can afford. I would like to get the 2bbl setup but my budget might not allow that at this time. The HEI mod might be more within my price range at this moment but I'll keep an eye out for 2BBl carbs and manifolds.

Where can I find a transducer-style egr for my truck? Are there articles containing info on such EGR's?

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1986 Dodge D100

Oh, sorry, I meant to post the info for the EGR valve. Standard #EGV490. Check RockAuto.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

If I were you, I would hold off on the two barrel swap until you get everything else working good on the truck. The last thing you want to do is change the variables of why the truck is driving poorly by adding an intake manifold and carburetor swap to diagnosis what problems you already have.

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Casually looking for a Clifford hyperpak intake for cheap.

Thanks guys. This definitely helps. I'll definitely look at the timing chain and vacuum pod on the lean burn computer this week first. Then check out the mods and what is within my budget. I appreciate the advice all you guys offer on this forum. It truly has made a difference in how this daily driver slant has worked out for me.

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1986 Dodge D100

The easiest way to tell if it has a lean burn on it is to see if there is a vacuum advance on the distributor. Sounds like my 83-the people before me said it wouldn't get out of its own way.In Texas a 83 doesn't need a convertor and it was gone before I got it and the carb was replaced with a non-lean burn 2 bbl. Just putting a stock 74 electronic distributor with GM HEI and a new timing chain made all the difference in the world. I had to change the rear end and now the speedometer reads 10 mph low at 55-and in OD the tach reads 1,000 rpm-it pulls.Ran it from TX to Il and only high head winds or semis drafting me pulled me down and I never ran it over 1500 rpm,( which comes out to 80mph) Even thru the high plains in NM at 4000+ feet of elevation it ran great.Now this is all on a worn out engine.But you will run across the problems of pushing a wall down the road as far as wind resistance goes and the slant 6 has only so much power in stock emissions form.

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I may be slow,but I"m ahead of you.

I have a 83- and left the computer in place,just wired in a GM HEI system and a stock 74 distributor.The distributor and timing chain made a world of difference,so did running synthetic oil.

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I may be slow,but I"m ahead of you.