Quick HEI wiring question

[Bushman66]

This is in a 1966 C10 that originally had a 292 I6 in it, now has a crate 350, but the same bellhousing and (3 bolt) starter from the 292.

Picked up a brand new AC Delco HEI distributor (P/N 93440806). It's in and I have a 12 gauge wire running directly to the IGN unfused terminal on the fuse panel (verified it gets 12.6V when the key is in "RUN" position, 0V when "OFF"). I have the lead from the engine harness that went to the positive side of the coil taped up.

Do I need to make any changes on the 2 wires on the engine harness that run to the solenoid? (i.e. do I need to remove anything, or can I just leave them as they are before I start it up?) I don't want to fry anything...

Thanks!

[Andy4639]

A REAL EASY, CHEAP, AND PRACTICAL UPGRADE YOU CAN DO TO ANY OLDER G.M. VEHICLE, WOULD BE TO DROP IN AN H.E.I. DISTRIBUTOR OUT OF A MID TO LATE '70'S CHEVY.
IT'S A STRAIGHT FORWARD SWAP, THAT IS ALMOST AS EASY AS PULLING THE OLD AND DROPPING IN THE NEW. ABOUT THE ONLY THING TO REMEMBER WHEN DOING THIS, IS THAT IN ORDER FOR THE H.E.I. TO WORK PROPERLY, IT WILL NEED FULL SYSTEM VOLTAGE. THE WIRE GOING TO YOUR COIL WILL NOT SUPPORT THIS KIND OF LOAD. THE BEST WAY TO DO THIS, IS TO PLUG THE HEI FEED WIRE INTO THE IGN. UN FUSED LOCATION ON YOUR FUSE BOX, AND RUN THE NEW WIRE OUT TO THE DISTRIBUTOR. WHILE DOING THIS, THE YELLOW WIRE GOING TO THE STARTER CAN BE DELETED ALSO. THE 2 WIRES CAN BE SNIPPED, OR TAPED AND TUCKED AWAY.
ONE OTHER THING TO REMEMBER WHEN DOING THIS, IS YOU WILL NEED A NEW SET OF PLUG WIRES. FOR A FEW BUCKS MORE, YOU CAN HAVE HIGH QUALITY WIRES THAT WILL GET ALL OF THE NEW FOUND POWER TO YOUR PLUGS.
FOR A LITTLE MORE POWER AND ECONOMY, PUT IN A HOTTER COIL AND AN AFTER MARKET ADVANCE KIT.
THIS EASY MODIFICATION WILL REWARD YOU WITH EASIER STARTING, BETTER GAS ECONOMY, AND LONGER PLUG LIFE. NOT TO MENTION THAT YOU'LL NEVER HAVE TO MESS WITH THE POINTS SYSTEM AGAIN.

[Bushman66]

Thanks. OK, from reading this it says the yellow wire CAN be removed, but it doesn't hurt anything to leave it in place, since I'm pulling 12V from the fuse panel, correct?

[Andy4639]

Originally Posted by Bushman66

Thanks. OK, from reading this it says the yellow wire CAN be removed, but it doesn't hurt anything to leave it in place, since I'm pulling 12V from the fuse panel, correct?

Correct. It want hurt a thing as long as it doesn't make contact with metal. You need to either cut the ends off and tape are make sure you tape up the connectors good. I always just clip the wires you want never go back to the old style after driving it. Plus it cleans up the harness nicely to.

[ray_mcavoy]

Originally Posted by Bushman66

Thanks. OK, from reading this it says the yellow wire CAN be removed, but it doesn't hurt anything to leave it in place, since I'm pulling 12V from the fuse panel, correct?

That's correct. The yellow wire can be left in place on the starter solenoid and won't hurt anything since you have taped up the end that used to connect to the + side of the coil. The purple wire attached to the starter solenoid needs to remain in place unchanged since that's the one responsible for cranking the engine regardless of the type of distributor.

[Bushman66]

Thanks guys. I left it and used heat shrink tubing to hide it. Fired up first crank, runs much better than with the points!

[Andy4639]

Originally Posted by Bushman66

Thanks guys. I left it and used heat shrink tubing to hide it. Fired up first crank, runs much better than with the points!

I bet it does sir! Good deal.

[maverickmk]

Sorry for hijacking this thread, but I found this picture in the FAQ section. I am putting HEI in my truck as well and would like to know where I pick up power from on the fuse block? I have q 1969 GMC.

[ray_mcavoy]

Originally Posted by maverickmk

Sorry for hijacking this thread, but I found this picture in the FAQ section. I am putting HEI in my truck as well and would like to know where I pick up power from on the fuse block? I have q 1969 GMC.

You'll want to plug the HEI feed wire into one of the two 1/4" blade terminals marked "IGN Unfused", located near the upper right corner of the fuse box as shown in that picture.

Although unfused, that circuit is protected by the main fusible link that should be located in the engine compartment near the positive battery terminal / junction block on the fender. So as long as you stay with the same gauge wire as the rest of that circuit (typically 12 gauge) you don't have to add an inline fuse to the HEI feed wire. That's how GM usually wired up the HEI distributors (no inline fuse) in the vehicles where they were stock equipment.

[maverickmk]

Originally Posted by ray_mcavoy

You'll want to plug the HEI feed wire into one of the two 1/4" blade terminals marked "IGN Unfused", located near the upper right corner of the fuse box as shown in that picture.

Although unfused, that circuit is protected by the main fusible link that should be located in the engine compartment near the positive battery terminal / junction block on the fender. So as long as you stay with the same gauge wire as the rest of that circuit (typically 12 gauge) you don't have to add an inline fuse to the HEI feed wire. That's how GM usually wired up the HEI distributors (no inline fuse) in the vehicles where they were stock equipment.

Fantastic, thank you for the quick response.

[ray_mcavoy]

Originally Posted by maverickmk

Fantastic, thank you for the quick response.

You're welcome!

Another option for feeding power to the HEI is to locate the stock resistance wire on the firewall bulkhead connector, extract that wire/terminal from the connector, and replace it with a new terminal crimped onto a section of 12ga wire that you route to the distributor. This method is electrically equivalent to plugging into the fuse box "ign unfused" terminal, but it avoids having to run the new wire through an added hole/grommet in the firewall. For this, you'll need a Packard/Delphi 56-series male terminal to crimp onto the wire and fit into the factory bulkhead connector.

[Bushman66]

I ran a 12 gauge red wire from IGN Unfused to the hot terminal on the HEI. I used an insulated female spade connector at the fuse box with heat shrink tubing to help hold the connector on the wire. Loomed the wire to the firewall and passed it through a rubber grommet in the hole the manual choke used to reside.