How to convert an HEI ignition to 7 wire computer control

Parts needed:

• 7 wire ignition module, mid 80's V8 chevy engines pretty much all had them and they are around $16 so no point in getting a used one.
• spade terminals small enough to go over the pins on the module, get them at the auto parts store when you get the ignition module so you can make sure they will go on without hitting each other.
• 4 pin weatherpack connector, optional depending on if you want it to be easy to take apart.

First thing is take the cap and rotor off the distributor. then take the advance weights and springs and any other stuff off you can get free.

also take out the old module and the condenser to get them out of the way. you now need to lock the ignition so it can't move on the mechanical advance assembly, either weld it solid, drill a hole in it and bolt the 2 plates together so they don't move anymore or make a plate to fit over the pins to hold them in place. The vacuum advance can be left on there but I recommend bending the vacuum fitting over on the end of it so it can not be hooked back up accidentally.

If you put the new module in place the pins line up but both bolt holes are out of line, the easiest thing to do is drill out both holes in the new locations and just use a bolt and nut in each new hole to hold it in place. don't forget to hook up the condenser and power wires back up to it and put the grease under it before you bolt it down.

Once you bolt it down you need to cut the plug off the magnetic pickup wires and put on spade terminals on the wires. also you need 4 other wires 3 of them need spade terminals on the end of them and either make up a plug for the other end or use a weathercock connector to make it look factory like, the ground wire can just be hooked up to the same place the other ground wire is hooked to on the condenser's mounting screw. Hook them up like it shows in the diagram above and you should be all set. I cut a small notch in the base near the vacuum advance housing to use for my new wires to come out of but the can be drilled and ran out the bottom of the housing or wherever will look best. Once they are hooked up put the rotor back on and the cap. The battery wire and the tach wire are still in the same positions on the cap and the old coil will still connect to the same wires it was hooked to before. Now you can hook up the new connector coming out of the distributor to whatever computer you plan on using and it can control the timing