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e015475 · 02-09-2019, 12:58 AM

A little progress this week.

Pulled my engine wiring harness out of the truck and shortened all the wires that needed it.

I mounted the PCM to the left of the steering column under the dash, and I didn't have to extend any wires in a factory harness, only shorten a dozen or so.

After I shortened all the wires that needed it, I unpinned PCM red and blue connectors to clean up the tangles at the PCM.

I took the wiring harness and taped it to the workbench in kind of a 2D approximation to how it will fit in the truck. Since I was changing the injector connectors from the EV6 type to the earlier EV1 type, I included the fuel rail to get the proper spacing on the injector connectors

Here is the fuel rail with the new connectors installed. I didn't trust the Russel adapter that went from the factory push-lock connector to a -6 AN fitting for the fuel supply, so I cut the fuel rail near the fuel damper thingy and put a Swagelok fitting on it. I'm not a big fan of compression fittings, but my son says he uses them all the time on quite high pressure lines and has never had a problem, so I will give it a try.

I loomed the modified harness with ICO-flex mesh loom I bought from Aircraft Spruce (they sell it by the foot - about $15 for the whole harness). I used the non-split mesh loom on the injector leads since I had to remove the connectors anyway, but the split loom looked so good in the other locations, I'd use it everywhere next time.

Here is the harness ready to go back into the truck after I check all the pin-outs on the PCM connectors and verify my grounds.

All told I have about 25 hours in modifying a factory harness. If I had it to do over again, I'd order a new one.

My idea of using a 3.5" mandrel bend for an air inlet duct for the engine was a pipe dream. (pun intended) Despite having a GMC radiator that sets deep in the support, a thin fan shroud, and my engine moved back an extra two inches, I was short about 2 inches. Plan 'B' is a silicone coupling, so I ordered one, but it came in and was the wrong inlet size. The correct one will be here in a couple days and I can finish fabing the inlet.

02-09-2019, 12:58 AM	#104
e015475 Registered User Join Date: Nov 2013 Location: Show Low, Arizona Posts: 761	Re: 49 GMC Five Window A little progress this week. Pulled my engine wiring harness out of the truck and shortened all the wires that needed it. I mounted the PCM to the left of the steering column under the dash, and I didn't have to extend any wires in a factory harness, only shorten a dozen or so. After I shortened all the wires that needed it, I unpinned PCM red and blue connectors to clean up the tangles at the PCM. I took the wiring harness and taped it to the workbench in kind of a 2D approximation to how it will fit in the truck. Since I was changing the injector connectors from the EV6 type to the earlier EV1 type, I included the fuel rail to get the proper spacing on the injector connectors Here is the fuel rail with the new connectors installed. I didn't trust the Russel adapter that went from the factory push-lock connector to a -6 AN fitting for the fuel supply, so I cut the fuel rail near the fuel damper thingy and put a Swagelok fitting on it. I'm not a big fan of compression fittings, but my son says he uses them all the time on quite high pressure lines and has never had a problem, so I will give it a try. I loomed the modified harness with ICO-flex mesh loom I bought from Aircraft Spruce (they sell it by the foot - about $15 for the whole harness). I used the non-split mesh loom on the injector leads since I had to remove the connectors anyway, but the split loom looked so good in the other locations, I'd use it everywhere next time. Here is the harness ready to go back into the truck after I check all the pin-outs on the PCM connectors and verify my grounds. All told I have about 25 hours in modifying a factory harness. If I had it to do over again, I'd order a new one. My idea of using a 3.5" mandrel bend for an air inlet duct for the engine was a pipe dream. (pun intended) Despite having a GMC radiator that sets deep in the support, a thin fan shroud, and my engine moved back an extra two inches, I was short about 2 inches. Plan 'B' is a silicone coupling, so I ordered one, but it came in and was the wrong inlet size. The correct one will be here in a couple days and I can finish fabing the inlet.