LS Conversion wiring 69 Firebird?

[jlwdvm]

I'm at the point on my project where I am starting to run the Spertech wire harness to my Texas Speed LS3. I ran the harness through the blower motor hole to get it into the car and under the dash. I will also be mounting the coils under there as well. I am wondering what I will do with the original 2 wiring harnesses that were for the original motor and light harness. I suspect that the light harness will stay, but what about the engine harness? I will be relocating the battery to the trunk as well. Positive wire still terminate at the starter?

[Vince@Meanstreets]

Originally Posted by jlwdvm

I'm at the point on my project where I am starting to run the Spertech wire harness to my Texas Speed LS3. I ran the harness through the blower motor hole to get it into the car and under the dash. I will also be mounting the coils under there as well. I am wondering what I will do with the original 2 wiring harnesses that were for the original motor and light harness. I suspect that the light harness will stay, but what about the engine harness? I will be relocating the battery to the trunk as well. Positive wire still terminate at the starter?

I usually pull all the unused pins/wires and seal with RTV.

Yep, terminate at the starter. You can run a feed wire off the starter OR use a bulk head on the firewall....near the starter.

[jlwdvm]

I suspect most of the light side of the harness is used and very little of the engine side of the harness is used? I'm thinking about replacing the majority of the wiring anyway. Will anybody make a custom harness that only includes what is needed for the LS swap?

[Vince@Meanstreets]

There are a lot of sources for LS harnesses. Most are stand alone, 3-4 wire hook up.

Maybe someone will make a suggestion. I have used and recommend Speartech but they have been very busy lately and its bit me in the butt a few times.

[Sheck44]

I just received my PSI harness, and it looks like it is a VERY well executed harness, that is perfectly labeled

Steve

[jlwdvm]

Maybe I wasn't too clear...I have a Spertech stand alone harness that came with my Texas Speed LS3 already. I started laying it out and hooking it up to the motor. It is long enough to get it through the heater blower motor hole so it can be mounted under the dash. It also has extra long coil pack leads to relocate them. I'm wondering what to do with the stock wiring that comes off the original firewall bulk head. Wondering what gets removed/cut, and what stays and how to handle this. I will probably be replacing all of the wiring in the car front to back as well. Thanks!

[dhutton]

Originally Posted by jlwdvm

Maybe I wasn't too clear...I have a Spertech stand alone harness that came with my Texas Speed LS3 already. I started laying it out and hooking it up to the motor. It is long enough to get it through the heater blower motor hole so it can be mounted under the dash. It also has extra long coil pack leads to relocate them. I'm wondering what to do with the stock wiring that comes off the original firewall bulk head. Wondering what gets removed/cut, and what stays and how to handle this. I will probably be replacing all of the wiring in the car front to back as well. Thanks!

I usually replace the stock wiring with an AAW Classic Update kit. There are some wires that are not used but the updated fuse block etc are well worth it.

Don

[jlwdvm]

So if a guy is going to replace all of the wiring in the car, both in front of and behind the firewall, what should he do? AAW classic update...any other methods? I will be going with an aftermarket dash and gauge set as well.

I would imagine that the AAW is a labeled kit that will use some of, but not all of the wires coming out of the fuse block if a guy is using an LS? Would the headlight side of the stock wiring be the same...comparing a stock motor set up to an LS?

[sleepertime]

I am going to be using a complete AAW kit for all of the main car and a modified stock LS harness from speartech for the engine side with Dakota Digital guages.
I am looking forward to starting on it.

[Z06vette]

I'd recommend the AAW harness as well. You can pull the pins at the bulkhead for any leads that you dont want to use. Very good instructions and all the options you will likely need.