My 86 D100 runs great when I drive it around town and on the freeway. I can get it up to 65 and cruise along the freeway my only problem is when I go uphills it slows down. Soon I'm struggling to even stay at 50 with the pedal all the way to the floor. I've cleaned out the intake manifold, as one of the ports was completely clogged, fixed the heat riser in the exhaust manifold and installed a new manifold gasket and exhaust gaskets. New Cat, fixed the smog pump and egr works, when I open the throttle I see the stem rise. I checked the timing and set it to 12B and have my carb tuned to ~750 RPM at operating temp. So could my problem be that I live up around 5000 feet? Or is it that I'm expecting too much and my truck is heavy and my slant has a hard time pushing her uphills? Any suggestions? I love my truck and want to see her cruise up the hills with no problems as she's my daily driver.

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1986 Dodge D100

I didn't see where you said stick or auto. But I used to have a 78 super six when i lived in Utah, at 5000 feet. Yeah, it had no power. First, you need to disable the EGR, you need to use a distributor with a better timing curve (one optimized for power, not emissions) and a super six intake and free flowing exhaust. That will help get you more power, and it won't hurt the milage at all.

The performance drop at 5000 feet is not insignficant. The D150 would not pull a 5 percent grade in 4th, and in fact would not pull past 45 mph on such a grade at 5000 feet.

Eventually, we put in an Iskendarian cam, and learned to use some more rpm, and that actually got better economy and you could run 55 up the grades in 3rd gear.

We had a couple friends with 302 Fords and a 305 Chevy, and once loaded with something heavy, the little slant would walk off and leave them on the steep grades.

You could also consider adjusting the gears to a 3.73 or 3.91 which will help you get up the hills at decent speeds.

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'81 W150 on Propane... Oversize valves, Oregon Camshaft cam, 10:5 static CR, Distributorless ignition, megajolt timing controller, PowerTrax lockers.

It is a manual 833, 3 speed with an overdrive. When doing a distributor with a better timing curve, can I do the HEI upgrade? I see where other folks are getting better results from this.

I live in an area where I have to do a yearly smog inspection. Will putting a free flowing exhaust hurt me when I do a smog test?

When adjusting the gears, will I have to drop the trans to do this?

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1986 Dodge D100

Yes, Do the HEI, and if you can afford it do a 2 barrel upgrade. It made a world of difference in hwo mine drove.

Rick

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Cool, I'm getting some info on the HEI upgrade from this forum so I'll be getting parts starting this coming weekend for it. Also I think our local pick n pull has a slant six with a 2bbl carb I thought I saw last time I was there. I'll check it out. Thanks!

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1986 Dodge D100

Does this truck still have the stock lean burn ignition system and carburetor? Replacing that system will be the best upgrade you can do for your truck in terms or performance and fuel economy.

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Casually looking for a Clifford hyperpak intake for cheap.

I'm still a bit confused about the lean burn system but this truck has the computer on the driver side fenderwall. The 1945 holley has a vacuum hose running from the ported spark tube over to this computer. The carb has no electronics except for the idle stop solenoid. I believe this is the lean burn system, right? I keep reading that people have removed this system but I'm worried about removing it and failing smog inspections. Also does disabling the EGR mean that the EGR valve stays open all the time?

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1986 Dodge D100

Before you listen to the advice ANYBODY gives you, you need to determine what your emissions laws are and what they allow you to do to your truck. The advice we will give you will depend largely on whether or not you can disable the emissions systems or if you have to keep the emissions systems in stock condition. Does your truck have to pass a visual emissions component inspection?

Disabling the EGR valve would render it always closed.

By 1986, all Chrysler cars and trucks (except for very heavy duty trucks that never had a slant six) were equipped with the lean burn carburetor and ignition system. Not only were these systems notoriously problem prone when new, but by nigh on 30 years after the truck was built, who knows how the systems have been molested by previous "mechanics" trying to "fix" the truck or "improve" how it runs.

Your truck does indeed have a computer controlled carburetor and ignition system. If your carb is original, it will have wires going to the idle stop solenoid AND wires going into the float bowl to control the stepper motor that controlled the mixture.

Disabling the lean-burn system on your truck would require swapping carburetors to a non-computer-controlled carburetor and swapping your ignition to a non-computer controlled electronic ignition system. When converting form a lean-burn system, HEI is really the simplest ignition system to convert to.

Let us know what your emissions laws are and we can give you better guidance on how to improve your trucks performance. At this juncture, I would strongly advise against buying a bunch of parts and just throwing them at the truck. Find out what you can do first, and then we can tell you what to buy and how to proceed.

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Casually looking for a Clifford hyperpak intake for cheap.

not to step on any toes, but his truck may not have a computer controlled carb. My 87 D100 did not, nor did it have any wiring for a comp carb. Mine also has no O2 sensor. all this depends on the factory emmisions trim.



Kevin

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crossthreads are better than locktite

Then someone removed the lean burn system before you got the truck. By 86, all slant six powered vehicles had a lean burn system.

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Casually looking for a Clifford hyperpak intake for cheap.

like I said, not trying to start a fight but my truck is still running the spark control computer and the dual pickup distributor. It has no provisions for an O2 sensor or a feedback carb. Never did, the carb is and always was a standard issue 1945. According to my service manual whether or not the truck had a feedback carb and O2 was dependent on what emissions trim it had and where it was sold.

It's a moot point anyway. With or without feedback the computer stuff is crap. Mine will be leaving shortly, just need to find an electronic dist.

Kevin

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crossthreads are better than locktite

I understand about the toes, but there did not need to be an O2 sensor for the carb to be computer controlled. Are you positive there are no wires going into the float bowl?

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Casually looking for a Clifford hyperpak intake for cheap.

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1986 Dodge D100

OK, so it sounds like you need to keep everything LOOKING stock. If that is the case, I recommend you hollow out the catalytic converters and do a "stealth" HEI install and carb swap. Doing a "stealth" HEI swap and carb install means leaving all of the wiring and sensors on the motor, but switching the distributor to a standard electronic ignition distributor, gutting the lean-burn computer and placing the HEI module inside the lean burn housing, and reusing some of the original factory wiring to wire up the HEI unit. You will need to get a wiring diagram for your truck to be sure you are using the right wires, but it isn't that difficult. The EGR can be disabled by disconnecting the hose from the EGR valve and squirting some RTV sealant up the hose. Let it dry for a few hours before you plug it back in. You want a solid plug to form to block the vacuum from operating the EGR valve.

Bear in mind that this will definitely qualify as "tampering" under your State's laws. You will be performing these modifications at your own risk.

The other option is to try and get the lean-burn system operating as well as possible. Not an easy task. If you choose this option, you will absolutely HAVE to get a factory service manual for your truck. You should also check and make sure that the vacuum pod on the computer still holds a vacuum. The timing and carb MUST be adjusted to factory specifications.

Other things to check are the typical wear issues for a 30 year old truck- timing chain stretch, potential slipping of the outer vibration dampener ring (which will give an incorrect timing reading), etc...

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Casually looking for a Clifford hyperpak intake for cheap.

Sounds good. I think I'll check the chain stretch next weekend. I like the idea about the stealth HEI mod and keeping it looking stock.

If i hollow out the Cat will that hurt my smog readings?

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1986 Dodge D100