I have an 85 D100. I want to isntall an MSD ignition, What problems will I have regarding the factory spark control computor

I really have NO idea, but from what I have heard, the msd would probably make a mess of the signals, but I am sure someone will tell you soon.
just keep asking stuff!

Do you still have the lean burn dist installed (two magnetic pickups?)

The magnetic pickup wires (green and purple) will not work with the dual pickup dist, they will not be used unless you swapped in a standard electronic dist. Instead, you use the small gauge white wire "points/amplifier trigger wire".

The small gauge white wire from the MSD connects to the original coil negative wire.

The small gauge red wire from the MSD connects to your original coil positive wire.

Heavy gauge red and black wires from MSD to battery + (red) and - (black).

Small gauge orange and black wires from MSD to coil + (orange) & - (black).

MSD Install Instructions

-S/6

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The "Silver Bullet"
87 Ram D150

http://www.slantsix.org/articles/leanbu ... rticle.htm

This will show you the correct distributor to use.

Your factory 'spark control compcomputer commonly called 'lean burn', the names mean the same thing.

If you have the factory distributor still, you will want to replace it with one from a pre-1980 slant six car or truck. 1973-1980 is your best bet.

The other parts of the wiring diagram don't really apply if you are using an MSD box. The MSD essentuaessentiallys the ECU in the wiring diagrams.

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1980 Aspen 225 super six

The MSD is essentially the ECU, BUT, it will work with the lean burn computer if all is still functioning well. The LB computer will still control spark advance, but spark output (multiple, capacitive discharge and voltage) will be dictated by the MSD box & coil.

Otherwise, if you plan to swap to a standard EI dist and a 'regular' carb, the MSD makes the conversion quite painless in the wiring department. With a standard EI dist, the white wire from the MSD is not used. Instead, the magnetic pickup wires (purple and violet) connect to the single magnetic pickup on the standard EI dist. No ballast resistor necessary. The rest of the MSD wiring stays the same as above.

-S/6

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The "Silver Bullet"
87 Ram D150

Do I need a vacuum advance?

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There is no problem that cannot be solved by the proper application of thermo nuclear weapons

Yes, I don't remember why, but everything I've heard says that distributor advances are a good thing.

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My car may be slow to sixty, but at least it's been reliably slow to sixty for more than thirty years.

yes, you need vac advance to keep your mileage up when part throttling. Me, I'd just chop off all the leanburn crap, use I1 + I2 wires to feed up the MSD box (smaller red wire) and throw in a regular electronic distributer (just one pickup, mech counterweights and vac advance)

In my personal experience, going thru the pain of wiring the heavy red and black wires straight to the battery makes diffrence.

Last week my heavy + cable, the one that goes to the starter, welded itself to the front branch of my split headers. I dunno why my car ain't went on fire, but my ignition did keep up its work during this mess. I couldn'tt believe that when I looked under the hood, cuz the slant wouldn't start after parking. When I popped the hood up and saw what was going on underneath, I went

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Juan Ignacio Caino

Please use e-mail button istead of PM'ing. I do log in sometimes but I'll be answering quicker thru e-mail.