HEI wire

[lts70]

So my dad and I put an HEI on my 70 SWB when I was 5 years old. 25 years later I started having HEI problems. This truck has been my daily driver for the last 15 years. I went ahead and put a brand new Distributor in the truck. That is when I noticed this, see picture below with large to small wire splice.

Is this bad?

What do I need to do, run thicker wire?

Why has it ran fine for the last couple decades like this?


Here is a link with pictures of my new distributer and engine bay

http://67-72chevytrucks.com/vboard/s...d.php?t=551274

[Wrenchbender Ret]

It looks like it is hooked to the resistor wire. That is not good but I have seen them run like that before. I go in back of the ign. switch & scrape soom insulation off the pink wire. Then solder a 12 gauge wire to it & run it to the bat side of the HEI. Lots of guys hook it to the unfused outlet on the fuse block but I like the direct hookup.

[davepl]

You need to run a new lead (probably 12 gauge or better, not sure) right from that distributor all the way to the "IGN UNFUSED" terminal of the fuseblock.

It'll run as is, probably, but you'll get a lot better spark energy if it doesn't have to fight the resistance that was built in to protect the old breaker points.

[lts70]

What is the resistor wire for? Looking at it closer the same color and size of wire comes out of the wire harness at the same place as the one in the picture comes from. Only it is pluged into my electric choke on my edelbrock carburator. If you look hard y.ou can actualy see it in the picture hugging the bottom of my valve cover.

[oldblue1968chevy]

I think the yellow wire is for the points setup. Ive read on here it doesnt supply a full 12volts. Like said before run a wire from ignition unfused on the fuse box

[lts70]

How has it ran like that for so long, and continues to run?

I am definalty running a new wire.

Should I just cap the old wire?

[davepl]

The resistor wire is for points ignitions only. I believe it is there to limit the amount of current that passes through the breaker points.
Posted via Mobile Device

[lts70]

Would this cause my truck to stumble a bit on take off?

What kind of problems or symtoms would this bad connection cause?

[davepl]

Hard to say. I'd expect it would have the most problems, if they were related to spark energy, at peak torque under max load, because that's when its hardest for the spark to jump the gap.

I wouldn't look for a reason to fix it, just fix it. If it solves the problem, great! If not, at least its correct now and it rules it out. It'll only take a few minutes to do it right.

[midniteblues]

once fixed you will notice a differance before I did the bigger wire in the kids truck it seemed too run very sluggish and I didnt understand why. I ran the big wire into the fuse box and boy what a differance especailly when it was wound up for fun

[lts70]

I am not looking for a reason not to do it. I like little projects like this that may improve preformance at no cost

I was just courious because this is the second truck I have had this motor in and I just cant get it to not stumble out of the blocks in this second truck. I am reaqly hoping this is the cause.

[PanelDeland]

http://67-72chevytrucks.com/vboard/s...ad.php?t=17403

http://67-72chevytrucks.com/vboard/s...d.php?t=148346

These threads will help you wire it like factory.

[brenthiggins]

If the resistor is still in the circuit you are not getting 12 volts to the distributor. I did the same thing on my 70 model earlier. Used the same wire just removed the resistor. Soldered the connections and it works fine. I also found out that if you run points and not the resistor you will be stranded soon. Thus my change to HEI

[lts70]

Thanks for the links Paneldeland, very good write ups. I am going to get the new fire wall wire harness connector and re-run thicker gauge from there to the cap.
Posted via Mobile Device

[lts70]

It looks like one of my yellow (old points) wire feeds is running my electronic choke. Should I leave it be or run it from a different location and wire?
Posted via Mobile Device

[VetteVet]

Originally Posted by lts70

It looks like one of my yellow (old points) wire feeds is running my electronic choke. Should I leave it be or run it from a different location and wire?
Posted via Mobile Device

There are 2 wires that go to the ignition coil Plus terminal. One is the resistance wire which has been discussed and the other is a wire from the starter R terminal usually it is yellow. This wire is designed to give the coil a full 12 volts during starting for a hotter spark. After the engine starts there is no voltage on that wire unless it is connected with the resistance wire which also goes to the coil plus.
The choke also requires a full 12 volts to work and it is hot all the time when the key is on, otherwise the choke will not work properly.The spring will not open the choke and the engine will run rich. You can run the choke off the other ign unfused terminal but do not wire it to the ignition wire that goes to the distributor. Any other key on 12 volt source will work as well, as long as it will support 10 amps or more.

[lts70]

When I get home from the inlaws I need to tear into my wire harness, because I know both wires have juice to them while the truck is running. I know this because the wire going to my HEI has always kept the truck running and the other wire going to my choke came unpluged when I was timing the new HEI. When it came off it arked sparks on my valve cover and killed the truck.

[VetteVet]

Well it sure sounds like you are feeding the HEI off the resistor wire and maybe the choke as well. I would certainly feed the distributor off the fuse panel or the ignition wire at the key switch like wrenchbender does.
Before you do the rewire you could run a temporary wire from the battery plus terminal to the BAT on the distributor and see how the engine runs. Don't leave it on because it isn't switched and will run down the battery or maybe damage the distributor. Maybe you should go ahead and rewire the distributor and choke because you will have to do it anyway.

[lts70]

That's the plan. I am going to unwrap my wires going back to the firewall and see exactly what is going on, mostly because I am curious about what is going on. I will then rewire both the HEI and choke.

Thanks for all the help guys!
Posted via Mobile Device

[slikside]

subscribed

[lts70]

Well I peeled back my wiring harness and found that I have been running my HEI and my choke on the low voltage resistor wire. Sure enough it was the white braided wire that broke of into the two yellow wires. See pictures.

[lts70]

I am going to pick up some 12 gauge pink wire tomorrow. When I mesured out the original wire it looks like I will need exactly 6 feet.

I would like to pick up the original style conector and conector shroud for the conection at the HEI (See Picture). I tried to pry the old one open in an effort to possibly reuse but it was to brittle and cracked. Anyone know a part number for these?

[Davemotohead]

Just run a new wire from the Ign terminal on the fuse block,,I left my resistor wire in place just in case I ever run points again and ran a new wire for the HEI and it runs Great!

[lts70]

I am trying to clean up stray wires. I bought a new firewall wire harness conector and will tap in to the exact location the points set up came from. I know that I will never go back to points so might as well cut out what I dont need and keep things as tight as possible.

[Davemotohead]

Just run a new wire from the Ign terminal on the fuse block,,I left my resistor wire in place just in case I ever run points again and ran a new wire for the HEI and it runs Great!