Re: MSD Ignition
Jerry is pretty close to dead on the money on this one.
You can drive the MSD module off your current ignition, and you will be 100% emissions legal, and you will not affect the O2 air controller or the factory tach.
That is not the most effective use for the MSD, but it is worlds above what you have now because it gives you real CDI ignition power.
Use MSD harness P/N 8874 for a very clean installation.
That harness, and two wires to the battery are all there is to it.
If the MSD unit fails, you just unplug the harness 8874 and plug your stock ignition back into the coil, and you are back on the factory ignition.
Then there is the MSD module, and MSD harness P/N 8869.
8869 lets you tap directly into the distributor, bypassing the air control hardware (effectively doing the John Nutter By Pass), and driving the MSD module straight off the distributor signal.
You will also need NAPA P/N ICC1 coil connector for this install.
This is easy, and it's a completely redundant ignition system that is fully CDI, and fully controllable.
You unplug the distributor from the stock wiring harness, and use P/N 8869 to connect the distributor to the MSD unit.
You unplug the coil from the stock wiring harness, and use P/N ICC1 on the MSD orange & black wires to connect the coil to the MSD module.
You unplug the two wire connector (red & white from the module).
Connect the two heavy wires from the MSD to the battery, and you are ready to rock.
If the MSD unit fails, you hook up the three stock connectors at the distributor, ignition coil and the module, and you are on your way again with the stock ignition.
If a guy were so inclined, he could switch back and forth for emissions testing, and have the best of both worlds.....
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