Well we were swapping a 5.3 into a 70 pickup and we are at the point where we need to connect power. All that I have is the wiring harness. Here are my questions:

1) I dont have the fuse block. . I am assuming that you can use the same fuse block that comes with our trucks.

2) The PCM diagnostic line. I have no idea how this is wired to our trucks (as far as the end that is going to the computer). Is it hard wired in the wiring or does it have a clip at the other end? Honestly I have never tried to follow the wire from the cab to the engine bay. How does it look at the other end.

3) How did you wire the ignition? I was looking at my Chiltons book and it looks like I need a just one wire going from the ignition to a 40 AMP ignition fuse, this would be to start it and another for the accesory. does this make sense to anyone.

Thanks for you help guys.

 

I got a hold of a stock fuse block from an '00 truck. That works pretty good. Otherwise, I'd recommend Nelson Performance (site sponsor) for a harness. He'll even graft ya one with your OBS fuse block. The only thing you'll need to splice is power ground, and (i believe) ignition.

I decided to use the stock stuff, and rework wiring using schematics.

 

If you decide you need a fuse block, I've got one from a 2000 Silverado, which includes the majority of a the harness as well. $75 shipped.

 

Good question, I am looking for the same answer.
1. Try to find the fuse bolck, I called the guy who pulled my engine and he still had it.

2. Are you asking about the OBDII port?? I wonder what lines I need to wire for those. I want to run two ports, one for my scan guage and the other on the passenger side for tuning.

3. Wiring seems to be kept secret. The pic shows how one harness will pulg up and the other is missing but the wires we need connect in that space?? I want to try to get my engine running but what wires do I need to connect/jump??

good luck the wiring seems like it will cause the most delays, and will effect the entire project.

3.

 

yeah does anyone have a step by step or any kind of write up on the fuse block splicing? i need this info as well.

 

where did that plastic white insert come from??

 

I sent the factory harness from my 05 5.3 donar truck to Dana at www.ls1wiring.com. The box went out weighing around 18 pounds and came back around 8. He will strip all of the stuff out that you dont need, run a new set of fuses to the stuff that needs it and wire in relays for the electric fans. They also did my tune to take out security and all of the emmisions controls. They will label and identify all of the hook ups and take all of the guess work out for ya. It also gives you a much cleaner look than having all of that wire that you dont need. I think the wiring harness and tune was around $400.00 but I had the motor in and was driving it in 2 weekends. The phone # is 814-323-3021

 

Hmm, I think I am going to contact him. I can do the tune but I started looking at the wires and I am thinking that this is going to be a pain in the ***. It would be nice to just have wires that you only need.

 

I have not had time to do mine yet, how ever, It realy shouldn't be too hard. I am using a F-bod comuter/harness. From what I have been told from 2 different buddies that have done LS1 swaps in to RX7's There really isn't much to get them fired up:

Splice power from an ignition source to the PCM
Find the fuel pump pin off the pcm and splice that to the fuel pump relay
Fans are grounded through the PCM so the relay ground goes to the PCM
OBD has 4 wires. Power, Ground, communication (can't remeber the 4rth right now)

I feel I am forgetting something else too.

 

Cool the OBD is the one that I am stuck on a little, those three make sence, but I wonder what the other one is for? I am going to look it up in the book.