PSI Harness Routing - K5
 

Trying to determine how and where to route the PSI harness for the LS3

Under the dash is possible but looks extremely tight with AC/ Radio/Dash panel, wiring ect....

Was considering using the center console to hold the ECM and small fuse panel - anyone feel like routing the harness this close to the trans will be an issue ?

From test fit it will be tight getting to the passenger side injector plug but it looks like it will barely make it

Also considering just buying a aftermarket repop since it has cup holders already installed and prevents me from using a good original one.

Re: PSI Harness Routing - K5
 

I put the ECM, fuse block and OBD port behind and under the glove box. I had to section the glove box a bit to fit the ECM. The fuse block and OBD port I made a bracket so you could see if the check engine light came on.
On a couple LS swaps I lengthened the check engine wires and mounted it in the gauge panel. See pic of Camaro gauge panel.
For the harness I try to hide all wires as much as I can. So I put a hole in the fire wall behind the engine. Pic of my 68.

Re: PSI Harness Routing - K5
 

Super clean setup LS

With haveing Vintage A/C room on the glovebox side is minimal / actually non existence really. Behind the radio or gauges is possible but very difficult to access.

Re: PSI Harness Routing - K5
 

I don't understand the appeal of having the computer inside the vehicle. They are under the hood on 100% of OEM applications.

Re: PSI Harness Routing - K5
 

My 94 Chev truck the ECM is behind the glovebox, just one example 100% is not correct. The ecm is in/under an enclosure in all under hood OEM applications. In a swap the enclosure it can be difficult to use, it is part of the stock fuse panel not being used, just not wanted for visual reasons or making a custom enclosure is more work than just putting it in cab.

Re: PSI Harness Routing - K5
 

On some of my LS swaps they are frame off and I have the time to clean up all the wiring and make it invisible. Most of my LS swaps are older projects and the stock wiring harnesses are junk and need to be replaced.
The exception to making the wires invisible is my 98 Wrangler LS6/4L60E swap. Wires running every where. ECM under the brake booster. Been bullet proof for almost 15 years.
See pic.

Re: PSI Harness Routing - K5
 

I personally like using the area between the grille and the core support. Hides the computer and keeps it cool. Wiring is less of an issue. Some of the modified factory harness do not have enough extra wire to use this option.

Re: PSI Harness Routing - K5
 

Of course the ecm can be installed bare under hood. Factory spent money to keep it away from the elements. Added research and pennies are spent on nothing by manufacturers without a reason.

Re: PSI Harness Routing - K5
 

Might relook at the core support area- just trying to keep it as clean as possible. Re-looked at under the dash - might try it one more time and see if I can make work.

The connection for the 6L80e is HUGE and will require like a 2-1/2'' hole in the firewall so I am considering that as well