harness routing
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From: San Antonio TX
Car: 1991 Camaro RS
Engine: 5.3 V8 LS
Transmission: 700R4
Axle/Gears: 3.42
harness routing
Hey i know there was a thread about routing a lsx harness under the a/c box but i cant seem to find it. Anybody know which one it was or have pics of how to do it. Thanks.
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From: N.E. Ohio
Car: 87 Gta
Engine: 5.3
Transmission: 4l60e
Axle/Gears: 3.42
Re: harness routing
We're you going the stock rout through the fender or did you want to drill a hole? Several threads/builds have showed it. But it's pretty easy either way. I just drilled a hole under the ac box
Thread Starter
Junior Member
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Posts: 29
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From: San Antonio TX
Car: 1991 Camaro RS
Engine: 5.3 V8 LS
Transmission: 700R4
Axle/Gears: 3.42
Re: harness routing
I ordered a harness from pocket for under the a/c i pulled the a/c box and it looks pretty tight down there. Just wanted to see what working for you guys.
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Joined: Aug 2004
Posts: 1,051
Likes: 4
From: Iowa
Car: 92 Camaro RS
Engine: LS1
Transmission: T56
Axle/Gears: 10bolt w3.42 Torsen
Re: harness routing
seen the same thread, i remember it said to make sure you leave some space between the hole and frame rail or water can run into the car.
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From: N.E. Ohio
Car: 87 Gta
Engine: 5.3
Transmission: 4l60e
Axle/Gears: 3.42
Re: harness routing
Right, I want to say I'm roughly an inch or so up off the rail. I no longer have a heater box so I just used one of the holes and opened it up to fit the harness. Right now I need to find the rubber grommet that fits the hole.
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From: new phila, oh
Car: 1990 RS
Engine: LS1
Transmission: T56
Axle/Gears: 3.73 9 bolt
Re: harness routing
I lengthened all of my wires and ran it under the AC/blower box and through the fender like it was from the factory. You can not see the big bundle of wire and I think it really cleaned up that part of the wiring. I did wrap the harness where it goes near the header under the box just for safe measure but have had no issues with it.
Thread Starter
Junior Member
iTrader: (1)
Joined: Feb 2013
Posts: 29
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From: San Antonio TX
Car: 1991 Camaro RS
Engine: 5.3 V8 LS
Transmission: 700R4
Axle/Gears: 3.42
Re: harness routing
Yea now that i think about it i should have ordered it for stock style mount. Anybody have any pics or their under a/c mount?
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Joined: Sep 2002
Posts: 3,685
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From: PA
Car: 86 Trans AM
Engine: LS1 (not stock...)
Transmission: Built T56
Axle/Gears: Strange 12-bolt w/ 3.73
Re: harness routing
I made an oval hole, and trimmed it out with rubber hose split down the middle lengthwise. I did it this way on two different cars and it worked good. If I do a third car, I will be building a completely new harness and probably go through the fender opening. Which I did use for some of the harness...HVAC stuff.

I had to notch the passenger hush panel to tidy things up.

Here's how it looks standing back a bit.

The harness is a LITTLE close to the header. Thats my only beef. I havent had any wires melt, but some of the split loom got a little toasty.
Justin

I had to notch the passenger hush panel to tidy things up.

Here's how it looks standing back a bit.

The harness is a LITTLE close to the header. Thats my only beef. I havent had any wires melt, but some of the split loom got a little toasty.
Justin
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From: San Antonio TX
Car: 1991 Camaro RS
Engine: 5.3 V8 LS
Transmission: 700R4
Axle/Gears: 3.42
Re: harness routing
Thats exactly where i was looking to route mine. I have no problem triming some stuff as i bought the car as a v6 RS roller. Thanks cruiser.
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From: Apopka, Florida
Car: 1989 Pontiac Trans Am GTA
Engine: cammed LS1
Transmission: Monster SS 4L65E
Axle/Gears: 9 bolt posi w/ 3.70 gears
Re: harness routing
I did mine a little different than Ghettocruiser did. I did mine under the A/C box and there's no need to cut interior panels where I did mine. There's more information on page 6 of my swap thread. I also found a nice 2" grommet to finish it off nicely. All of the information is on my thread. See the link below if you are interested.
Thread Starter
Junior Member
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From: San Antonio TX
Car: 1991 Camaro RS
Engine: 5.3 V8 LS
Transmission: 700R4
Axle/Gears: 3.42
Re: harness routing
Thanks dprest68. I was looking at that spot and may end up going with it to get away from the motor and the exhaust manifold.
Joined: Sep 2002
Posts: 3,685
Likes: 10
From: PA
Car: 86 Trans AM
Engine: LS1 (not stock...)
Transmission: Built T56
Axle/Gears: Strange 12-bolt w/ 3.73
Re: harness routing
I looked into doing it where dprest68 did. In the end, I couldnt fit the harness comfortably through there, and would also have had to extend it quite a bit. I used the stock LS1 harness.
My PCM is mounted in the exact spot where the factory ECM was.
The only reason I had to cut anything inside, was the way I taped my harness up. Had I checked the fit of things before taping, I would have done it differently. I only had to notch the hush panel a little. 1" x 1-1/2" maybe? It was the end of the build and I wasnt in the mood to mess with it anymore haha.
Having done this to two cars, on the off chance there is a third, I would make some changes. 1)Ide strongly consider a harness from Pocket, lengthened if available. 2) I would def do a round hole vs oval, and get a nice Seal It grommet or something.
All options will work well though!
J.
My PCM is mounted in the exact spot where the factory ECM was.
The only reason I had to cut anything inside, was the way I taped my harness up. Had I checked the fit of things before taping, I would have done it differently. I only had to notch the hush panel a little. 1" x 1-1/2" maybe? It was the end of the build and I wasnt in the mood to mess with it anymore haha.
Having done this to two cars, on the off chance there is a third, I would make some changes. 1)Ide strongly consider a harness from Pocket, lengthened if available. 2) I would def do a round hole vs oval, and get a nice Seal It grommet or something.
All options will work well though!
J.
Re: harness routing
Better late than never. Mine is just a little higher than ghettocruiser's. 2" round hole, insulated with 3/8 fuel line. Basically anywhere in the vicinity will be fine
Thread Starter
Junior Member
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Joined: Feb 2013
Posts: 29
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From: San Antonio TX
Car: 1991 Camaro RS
Engine: 5.3 V8 LS
Transmission: 700R4
Axle/Gears: 3.42
Re: harness routing
Thanks pocket. Got your harness in and everything was labeled and easy to hook up. No regrets lol, i havent been able to get the hole cut but i basically marked it where yours is. Thanks
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