The Stovebolt Site Forums The Shop Area Engine Shop '66 250 HEI conversion

I was changing the oil in my grandpaw's '84 C-10 with an integral head 250 yesterday, and I noticed that it has an electronic ignition distributor on it. Is it possible to put that style dist. on my '66 250 with out too much fuss and bother? There is a good junk yard near me, so getting all of the pieces in one trip isn't an issue, but what all do I need to get if that swap is possible? Also are there any wiring changes to be made and what do I specifically need to look for?

It is an easy, rewarding swap. The 75-77 had a separate coil. The 78 up is the best selection. Be sure it has mechanical & vacuum advance. Somewhere in the mid 80's they went to electronic advance mech. The unit is self contained so it's just a matter of replaceing your dist with it. Run a 12 gauge wire from the ign. term on the back of the switch. It's usually a pink wire. I scrape off some insulation & solder the wire to it. That way you dont disterb any thing else hooked to it. Plug the wire into the bat. term on the HEI. Regap the spark plugs to .045. Set the timing & you are ready for spark like a bolt of lightning. If you have a A/C comp. on that side you may have clearance problems.

I know its been almost two years since I initially asked this question, but I finally got around to making the swap now that I have graduated college. I also have the complete engine rebuilt and had 307 V8 pistons installed in addition to having the block bored out and the crank ground.

I'm having a problem getting the truck to start. I ran a 14 ga. wire from the pink wire (I believe that it is 14 or 16 ga.) to the batt. terminal on the distributor. I also put an inline fuse in the wire. So far it has blown a 15A and a 30A fuse, what size fuse should I have in the holder? I'm not too wild about playing the guessing game and stepping up fuses as I go along.

Try a bigger wire like 12 or 10 gauge. As a test run the new wire to an unfused male connection on your fuse panel. Also use an insulated female connector on the end you hook to the distributor.
If that gets you started then you know you have too much resistance in your current set up.

Do not put a fuse in the ign. circuit. Turn on the switch & useing a test light make sure there is current at the B term. Pull a plug wire off & put an old spark plug in it with a wide gap. Lay the plug on metal part of the engine. Crank the engine & you should get spark across the gap of the plug. If not your dis. needs fixing.

And as temporary test, wire the distributor straight to the battery with 10 gauge wire, no fuse. Bypassing the key and dash till you see if the distributor is good. If it starts, set the timing and lock it in place. Pull the temp wire to kill the engine and start working your way back to the key switch till you get it running again. Most switches do not send out ignition voltage in start position, that comes from the starter. Once you release the key back to run, the switch then provides voltage to the distributor. On the starter solenoid are two small post, one is from the key, the other goes to the distributor. You can replace that wire with 10 gauge and tie it to the new 10 gauge from the key switch.

Another option is to replace the key switch with one that provides ignition in start and run.

Joe