Need Engine Harness Recommendation

[69l46vert]

Hi All, Truck is 54 GMC with 72 GMC K2500 engine and drivetrain. (350/SM465/NP205. I finally started the truck's engine yesterday and it runs just fine. It was only hot-wired to test run but now I need to wire up the engine properly and so I'm looking for some recommendations for a basic engine harness. I have virtually nothing at all right now to start with so thought it would be simpler to just buy a basic universal type kit to get the job done. One more detail; I have a 10si in place of the original ext. reg. alt. Thanks for any help or ideas, Rick

[73kay]

I honestly just went to junkyard and pulled a 70s Chevy truck harness and installed it in my 53. I got circuits, fuses, very simple and matches the headlights, and fits a truck form factor for wire routing. Didn't cost me much and I ended up using the 70s headlight switch too. I also rewired the ignition saw to the stock key sw in the 53. That was pretty easy. Just an idea.

[_Ogre]

basic engine harness

if all your looking for is a ''basic engine harness'' for a carbed motor there are few wires
ignition power, starter power and a couple of sensors; nothing really bundled together
run individual wires and bundle them with the existing harness (they should be in the existing harness)

if your looking for a whole truck harness that will cover everything
ezwire, painless, aaw, speedway all carry universal harnesses
58 truk has an ezwire harness for extreme low cost

[69l46vert]

Thanks Andrew and Ogre. Does anyone know if I need a ballast resistor for the coil or is full 12 volts ok for that?

I suppose I should look ahead and get an entire truck harness as it will be needed eventually. I really have nothing to start with.

[73kay]

I converted my dizzy to hei which matched my 70s harness. Not sure about your setup. Just be careful with the coil. I accidentally left my ign sw pwr on to the coil while the truck was in the garage. Coil cooked and exploded. After that I went hei.

[_Ogre]

I suppose I should look ahead and get an entire truck harness

get a new one, it may have worked for 73kay, but imo installing a 45+ yr old harness is asking for trouble
hei conversion (if you have room) is the best thing you can do for your motor
you need the resistor if you stay with points, not for hei

[OrrieG]

I personally would not pull out a 46 year old harness to replace a 60+ year old one. Classic, LMC, etc. all have complete and partial harnesses. The engine compartment ones come configured for stock generator or alternator upgrade. If you choose to just do the engine one I would recommend using fusible link wires or a small fuse panel to protect the circuits. I completely rewired mine with a EZ harness, a search using the box above will turn up a number of Pro/Con treads on the different manufacturers.

[69l46vert]

I recently rebuilt a 69 Corvette and got a stock harness from Lectric Limited. It was very well made. All colours and lengths were spot on. Every plug and receptacle perfect. It was expensive at about 1,300 for everything but really was worth it.
That was a little different in that the car is stock so all the wiring was pre engineered for me. This time it looks like I'll have to think a little more for myself since this truck will be a crossbreed between a 72 and 54. A lot of details for me to learn about before this happens. I'l do some searching here to see the opinions.

I actually like the old points ignition system. The big stock HEI might not fit in mine since the motor is pretty far back. But as I'm typing you've just reminded me I have an extra MSD tach drive dizzy that is small diameter. That would probably work with a stock big truck tach. hmm. I do appreciate all the insight and suggestions. Thanks, Rick

[73kay]

Hahah well mine was a budget-minded option. I don't see too much issue with uses wiring IF its stock and hasn't been cut up by the previous owner. I went that route bc I already am familiar with them as I have a 76 c10. But I'll the rookie here and would trust what OrrieG says.

[DransportGarage]

I'm not a big fan of used GM wiring harnesses. I've had an '86 and a '93 Astro van in past years, and many of the accessories ceased to function while I owned them (power windows and power door locks vividly come back to mind). I remember that, in addition to overly sensitive temp sensors in the motors, crummy motors, etc., the wires going into the doors had a tendency to crack. Without even mentioning the crappy switches (oops, I mentioned them), overall, the electrical systems were budget-based when they were designed. Maybe if you go back far enough (to the 70s?) the problems aren't as bad, but I also don't recommend using a 40+ year old harness.

My choice? American Auto Wire (AAW) bought from Bailey's Garage, but others are great as well, as Ogre had said.

[_Ogre]

(power windows and power door locks vividly come back to mind)

having all those sweet features built into the door also means 25 wires in a 3'' door loom
i fixed the wife's dodge minivan door loom way to many times