Resistor wire on a 68?

[1968ChevyC30]

Having spent several hours scratching my head over why my new MSD #8360 "ready to run" distributor and MSD #8202 coil won't operate properly with my freshly built 327. I have spoken with MSD Tech as well as gone over the wiring diagrams, and remain baffled as to why this distributor won't work. As a test, I installed a used Accel electronic distributor without a ballast resistor using the MSD #8202 coil and all worked fine. I also went so far as to obtain another new MSD #8360 distributor only to have the same problem as with the first one. MSD states that a ballast resistor isn't used with their setup, yet the Accel unit requires one. This leads me to believe there is a resistor wire within the engine harness that I can't find within the diagrams I have. Can any of you offer any assistance with my dilema? Thanks in advance.

[FirstOwner69]

If it was not previously converted correctly to HEI, the wire from the bulkhead connector to the coil is a resistor wire. It can be taken out of service and a new wire run to the ignition unfused terminal (if I recall correctly) inside the cab or replaced at your discretion.

This thread should help. The "good part" starts at post 11.
http://67-72chevytrucks.com/vboard/s...d.php?t=148346

Another:
http://67-72chevytrucks.com/vboard/s...d.php?t=553330

[VetteVet]

The resistor wire on the stock truck from the factory is located in the firewall block by the master cylinder. it was an orange white purple originally but has probably faded over time to just a whitish cloth wire.




a Looking at the MSD website diagram The ignition wire from the key switch goes directly to the coil Positive terminal, so they don't show a resistor or wire in the circuit.


I would try running a 12 gauge wire from the IGN UNFUSED terminal on the fuse panel, directly to the coil positive, and try that.

[quick60]

I'm not sure about the photo. You have two wires identified by 1 and 2. But the resistor wire in question i am assuming by your description is the wire with the woven jacket on it?

[quick60]

Also does anyone have any suggestions on resealing the back of the wiring harness block once you install the new wire?

[CastIron]

On my 69, the woven wire is the resistor and runs down to the starter. Then it goes back up the coil as a regular wire. I don't remember the color, red or yellow? But I removed both wires when I installed a new HEI distributor and replaced it with a 12 gauge wire coming from the same spot on the bulkhead connector and going straight to the coil. I rewrapped the harness and it looks like it could be factory now.

['68OrangeSunshine]

The 20 Or/Wht/Ppl is the woven line in VV's above pic. [Its not numbered since the pic if from another discussion. It would be #3, maybe.] This line terminates with a split to two 20 Yellow wires, behind the block; one to the Starter and the other to the stock Coii (+) terminal. The 2 yellow wires are also redundant in electronic operations, and should be taped off, at least.

['68OrangeSunshine]

Originally Posted by quick60

Also does anyone have any suggestions on resealing the back of the wiring harness block once you install the new wire?

You could either pack it with non-conductive silicone grease, or use silicone RTV. Just remember to scrape any RTV off the contact surfaces after it dries.

I know the factory used some brown, waxy, sticky, smelly stuff back in the day. It was probably Bear Fat. Can't get it now due to environmentalism.

[1968ChevyC30]

Thank you for all of your responses. I ultimately wound up running a 12 gauge line from the unfused ignition lug on the fuse panel inside the cab directly to the coil and it resolved my issue with the MSD ignition system. Now that the engine is broken in and running, I can now concentrate on finishing the truck and posting photos of the net result of this complete body off full restoration with a few minor mods. Again, thank you all for your assistance. I'm very pleased to have found this forum and the generosity of the information willingly offered.