Chassis harness

[Mark69bird]

I been doing some research to see what options are out there. I thought I would ask here as well to see what people have done right and what have done not so right. This year I want to get a list of parts that I need to get my car wired. So my plan first started with a stock Pontiac block. Well as I got into my build I decided to change my plan. I picked up a LQ9 along with a TR6060 combo. Got this package at a great price. I also picked up a ricks resto tank. My car needs a chassis harness. I have the motor harness and I have a bowler harness for the transmission. I plan on taking the stock truck harness and removing what I don’t need. I know it’s a bit of work but I don’t mind. I know I can get a painless harness fitted for my 69 Firebird but that’s for a stock car and how much of that harness is useless because of the LS swap. I know they have a LS swap type harness but I’m trying to keep cost down. I also plan on running a Camaro fuel pump so I need to take this into consideration as well. From what I have been reading I’ll need a controller for that too. Any info would be much appreciated.
Thanks.

[joeko23]

AAW classic update harness. You will use at least 90% of the harness.

If you want the best for fuel control than you will need a vaporworx controller. It’s a returnless system that’s pwm. If you don’t want to spend the money on the controller you can setup a return style system that’s constantly pumping fuel.

[CarlC]

AAW classic update harness. You will use at least 90% of the harness.

If you want the best for fuel control than you will need a vaporworx controller. It’s a returnless system that’s pwm. If you don’t want to spend the money on the controller you can setup a return style system that’s constantly pumping fuel.

It is not recommended to use an external return fuel system with any modern fuel module. They can pump themselves dry, and that's not a good thing.

Nobody makes an engine harness that will seamlessly integrate into the chassis/interior harness of the car. Nor do the early f-body firewall bulkheads have enough extra cavities to accommodate all that is needed for engine monitoring, data bus, etc. Though not something that presses the EASY button, here's what I did:

1) Get an AAW Classic update kit.

2) Order from AAW an interior side and the two firewall side bulkhead plugs for a second gen f-body. The second-gen bulkhead has enough cavities for lots of extra circuits. Also order up a whole bunch of new terminals that can be used to put in new wires. Several good quality crimpers will be needed.

3) Layout the second-gen firewall bulkhead harnesses so that one side carries the engine/ecm data and other circuits that support the engine. This makes the engine harness removeable. Make the other bulkhead for lighting, wiper motor, etc.

4) Swap over the interior side bulkhead plug based on how the wiring is placed on the firewall side. There is no hard copy guide for this, just common sense. Triple check your work as it's no fun to fix a blinking dome light.

5) Add additional circuits to the interior side bulkhead that align to the fire wall side plugs. Route where needed.

A through knowledge of the ECM/engine wiring will be needed along with making your own wiring diagram of the bulkheads.

[Mark69bird]

It is not recommended to use an external return fuel system with any modern fuel module. They can pump themselves dry, and that's not a good thing.

Nobody makes an engine harness that will seamlessly integrate into the chassis/interior harness of the car. Nor do the early f-body firewall bulkheads have enough extra cavities to accommodate all that is needed for engine monitoring, data bus, etc. Though not something that presses the EASY button, here's what I did:

1) Get an AAW Classic update kit.

2) Order from AAW an interior side and the two firewall side bulkhead plugs for a second gen f-body. The second-gen bulkhead has enough cavities for lots of extra circuits. Also order up a whole bunch of new terminals that can be used to put in new wires. Several good quality crimpers will be needed.

3) Layout the second-gen firewall bulkhead harnesses so that one side carries the engine/ecm data and other circuits that support the engine. This makes the engine harness removeable. Make the other bulkhead for lighting, wiper motor, etc.

4) Swap over the interior side bulkhead plug based on how the wiring is placed on the firewall side. There is no hard copy guide for this, just common sense. Triple check your work as it's no fun to fix a blinking dome light.

5) Add additional circuits to the interior side bulkhead that align to the fire wall side plugs. Route where needed.

A through knowledge of the ECM/engine wiring will be needed along with making your own wiring diagram of the bulkheads.

Do you have some part numbers?
You saying to get the 2nd gen wire harness? Just want to make sure I’m reading this right and following correctly.
I know it’s not a simple quick connect and go. I figure the engine harness would be a standalone.
Thanks

[CarlC]

Get a 1st-gen wiring harness. Add the 2nd-gen bulkhead connectors. This is something way off the reservation and not on their website. No part numbers available.

[Hotwire]

I'm with you and understand what you're trying to do. I went the STUPID hard route of taking the underhood truck fuse box and repurpose it as my main, then integrated it to the chassis harness of my 64 Chevelle. It works well, but it took time and planning to get everything done. Main issue was the underhood harness has a lot of battery fed circuits so I had to turn a few into ignition fed or run separate relays to get ignition feed. The dash fuse box has the ignition fed fuses. I converted my headlight switch to ground feed, that runs the headlight relay in the fuse box. Nabbed a firewall grommet off a 2005 yukon as my passthrough, cut a 3.25" hole in the firewall behind the intake and fed the wires through.

If you do as you're planning, label EVERY wire coming out of the ECM and depin all of them. Untangle every wire and route it exactly as you want it to lay, you can use a heat gun to help get the wires to straighten out. Leave a little service loop at every component, I ran heat shrink up to every plug to clean up the look as well. Amazon has some great braided loom (alex tech) that is inexpensive and bundles the wires tightly, I just used junkyard split loom (serious ebenezeer budget) You can click on my build thread in my signature, wiring started on page 8 but there's a lot of talk in between, it's a long winded thead..

Attachment 196571

[TANKMASTERJ]

I used AAW classic update like many have. I used a stand alone LS harness from PSI.if I was doing it again I would have went Speartech or BP automotive. That. Being said the AAW is a great harness for chassis. You'll use most the interior portion as well as front and tail harness. Only thing you won't use alot of is the engine side of the firewall forward from bulkhead. As Carl and others have suggested you can just repin. I chose to just remove the un used wires and took advantage of those I could. Think secondary oil pressure and water temp. My LS stand alone feeds my tach and speedo. AAW has a provisions for speed sensor you could use. But let the LS Harness do tach and speedo and it has an oil pressure and water temp to the LS Harness but no output for gauges. So I used AAW wires for oil and water. I added a port for the AAW oil pressure gauge sender and my LS water sender was in driver head so I put in the passenger head a water sender for the AAW water temp gauge.
AAW has an accessory pigtail for power door locks and Windows and a couple other extra IGN and Accessories.
I'm using those and chose to add an EATON 5 relay 10 fuse panel in my trunk. Ingot it feeding two heated seats, fuel pump, stereo amp and one circuit to LS ign for ECM.
That trunk mounted panel has a remote control contactor between it and the battery so without remote it can be cranked but no fuel no ECM.
Theft prevention was my idea here along with an added benefit of relays for heated seats and fuel pump as well as stereo amp.
Just some thoughts

[Mark69bird]

Thx everyone for the suggestions. I really appreciate it. Sure helps.