Standalone harness
Speartech is good, clean, easy, but pricey.
Have you read the sticky on how to wire these things? LS engines are basically stand alone harnesses already so A LOT of what you pay for is just cleaning up the routing and snipping out what you dont need. For instance if you get a harness from the same vehicle as your engine and a PCM the PCM plugs into that harness. All thats required is hook up all the orange wires to 12v+ and the pink ones to 12v IGN, delete VATS and it runs. The rest of the wires are for things like gauges, fuel pump, fans etc.
Easiest way to do it is remove all the tape and wrap etc. Lay it all out on a table. Remove anything you dont want ( AC? EGR? Cruise? etc etc. ) then put whats left on the engine and plug everything in. Route it as you want it. The leads that dont make it to the PCM you extend, the ones that are too long you shorten and thats that.
Route is as per your own design/taste/whatever theres some extremely neat home grown harness jobs on this site. Save the 1500 bucks.
This link is EXTREMELY handy for building a harness. If you decide to do it there are many other great links i can post. Lemme know
https://ls1tech.com/forums/conversio...swap-faqs.html
Have you read the sticky on how to wire these things? LS engines are basically stand alone harnesses already so A LOT of what you pay for is just cleaning up the routing and snipping out what you dont need. For instance if you get a harness from the same vehicle as your engine and a PCM the PCM plugs into that harness. All thats required is hook up all the orange wires to 12v+ and the pink ones to 12v IGN, delete VATS and it runs. The rest of the wires are for things like gauges, fuel pump, fans etc.
Easiest way to do it is remove all the tape and wrap etc. Lay it all out on a table. Remove anything you dont want ( AC? EGR? Cruise? etc etc. ) then put whats left on the engine and plug everything in. Route it as you want it. The leads that dont make it to the PCM you extend, the ones that are too long you shorten and thats that.
Route is as per your own design/taste/whatever theres some extremely neat home grown harness jobs on this site. Save the 1500 bucks.
This link is EXTREMELY handy for building a harness. If you decide to do it there are many other great links i can post. Lemme know
https://ls1tech.com/forums/conversio...swap-faqs.html
Launching!
Joined: Sep 2009
Posts: 250
Likes: 3
Guy before me nailed it.
The stock harness is basically stand alone. Nothing really to cutting it down.
It'll end up as clean as you'd like AND as an added bonus, you can located the PCM wherever you want.
I think there were 8 wires that are fused if going by factory fuse setup. This can get cut down quite a bit by combining like items.
I think I ended up spending 16 hours playing with my own harness but I'd say about half of that was spend walking between car and FSMs inside
The stock harness is basically stand alone. Nothing really to cutting it down.
It'll end up as clean as you'd like AND as an added bonus, you can located the PCM wherever you want.
I think there were 8 wires that are fused if going by factory fuse setup. This can get cut down quite a bit by combining like items.
I think I ended up spending 16 hours playing with my own harness but I'd say about half of that was spend walking between car and FSMs inside
GMPP's Ls controller. less than a grand and comes with all sort of goodies. https://store.gmperformanceparts.com...umber=19201861
Thread Starter
TECH Resident
Joined: May 2005
Posts: 983
Likes: 0
From: 8000DA Land
GMPP's Ls controller. less than a grand and comes with all sort of goodies. https://store.gmperformanceparts.com...umber=19201861
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Teching In
Joined: Sep 2009
Posts: 33
Likes: 0
I did my own harness and I'm the last person you'd have thought would even attempt it. But I didn't have the $$$ for a standalone and I had the time. It worked out well because I re-routed a lot of the wiring off the top of the engine and cleaned it up nicely.
The key is getting a large clean work area and a good schematic and familiarize yourself with the harness. There are only so many plugs and most will remain. So the rest is routing and eliminating unwanted wires. And work on one wire at a time. Before you know it, you'll have the harness you want and you still have a grand in your pocket to spend on upgrades.
The key is getting a large clean work area and a good schematic and familiarize yourself with the harness. There are only so many plugs and most will remain. So the rest is routing and eliminating unwanted wires. And work on one wire at a time. Before you know it, you'll have the harness you want and you still have a grand in your pocket to spend on upgrades.
Did Speartech pricing go up? Their website states $750 for a LS1 stand alone Harness.
I'm researching my options and besides doing it myself, I have narrowed it down to a Speartech or Painless (60509 or 60508) harness. Both are listed around the same $$ on their respective web sites. I've seen many glowing reviews of the Speartech harness but I haven't found any reviews (still looking) of the Painless harness.
edit: Looks like Painless has a $100 rebate going for the next month that includes harnesses.
I'm researching my options and besides doing it myself, I have narrowed it down to a Speartech or Painless (60509 or 60508) harness. Both are listed around the same $$ on their respective web sites. I've seen many glowing reviews of the Speartech harness but I haven't found any reviews (still looking) of the Painless harness.
edit: Looks like Painless has a $100 rebate going for the next month that includes harnesses.
Last edited by iflytii; Feb 25, 2010 at 07:11 AM.
There website is still $450 i just sent them an e-mail to see what they can do for me. They also offer the TPS pedal harness and such if you need that. And will lengthen the PCM connector so you can hide the computer inside the vehicle for a clean engine bay.
there is a guy on ebay that makes wonderful harness!
I bought one from him. I'd post a link but the mods would just erase it. Look up techrods on ebay.
100% all new wiring and pig tails. he made one up for me with the 4l80e harness and dual electric fans for right at $500. comes with relays for the fuel pump a fuse box everything! very nice harness.
here's a pic of his harness
I bought one from him. I'd post a link but the mods would just erase it. Look up techrods on ebay.
100% all new wiring and pig tails. he made one up for me with the 4l80e harness and dual electric fans for right at $500. comes with relays for the fuel pump a fuse box everything! very nice harness.
here's a pic of his harness
GMPP's Ls controller. less than a grand and comes with all sort of goodies. https://store.gmperformanceparts.com...umber=19201861