LS1 engine harness [Archive]

mightymouse713

12-26-2007, 11:38 AM

I have a 99 LS1 and T56 setup I am putting into a 68 Camaro. I purchased the parts seperately without a harness. I have an opportunity to buy an 04 GTO harness that was setup for a 6 speed. Will this harness work for my setup? I can send harness out for the mods if needed.

trapin

12-26-2007, 12:14 PM

Give Speartech a call...they would know. And they're the best to modify it too. You never know...it might be cheaper just to buy one directly from Speartech already modified.

70bird

12-30-2007, 11:18 PM

I used the one from Painless, good quality, requires 1998 pcm. about 500 bucks but a big time saver

DCx

12-30-2007, 11:49 PM

bout the only difference i know of off the top of my head is the gto uses a 5 wire maf. the early camaro ls1 you have uses a 3 wire and an air temp sensor.

matty b

01-01-2008, 08:34 PM

gto harness uses a totally different computer than the ls1. ls2 also has the map sensor up front, cam sensor up front, different maf, air temp, injector connectors ect. Its swappable but not worth the time and effort to do it. Any gen 3 harness will work without any mods necessary.

pist0lpete

01-06-2008, 12:06 AM

I believe the 04 GTO was actually an LS1 so you should be good to go I would pick up the harness if the price is right.

kurider

01-06-2008, 09:11 AM

No, I had an 04 GTO LS1 converted and was told its completely different than an F-body harness. Was told it the GTO harness required a lot more to convert than an Fbody.

mightymouse713

01-06-2008, 10:11 AM

I ended up buying this one on another forum:

this is a ls1 conversion harness done by speartech
they installed a fuse box,inside diag port,and check engine light,also instaled the fuel pump relay
i am taking it out now but here are some pics of it as it comes out 450.00 shiped it is for a auto car also have 2 pcms for sale.

I bought it even though I have an M6 setup, he said it can be used as a stand alone. I bought both pcms and the harness shipped for the price stated. It sounded to good to pass up since it was redone by speartech. I have seen just the harnesses for 250+ and would need mods so it seemed worthwhile. Can anyone give me input as to using this on my LS1/T56 setup?

https://static1.pt-content.com/images/pt/2008/01/attachmentphpattachmentid113504d11984447-1.jpg

mightymouse713

01-08-2008, 10:01 AM

I am curious to what differences there are on the wiring harness of a 98 to a 99+. Are there differences I will be dealing with since I am using a 98 PCM/harness on a 99 LS1 engine? The harness was modded by speartech and PCM flashed for 98 setup.

merriman44

01-08-2008, 11:05 AM

My my my well if this isn't the the most flip flopping thread I've seen in a while. Any body with REAL experience want to get in the final word? Preferably someone who has personally worked on both.

mightymouse713

01-15-2008, 03:06 PM

It seems everything will work as is....just have to use a 98 coolant sensor.

70bird

01-15-2008, 04:46 PM

It seems everything will work as is....just have to use a 98 coolant sensor.
Are you using 99up or 98 PCM?

If you are using 98: check here about about fuel injectors and PCM pulse times. https://www.pro-touring.com/forum/showthread.php?t=38604