The "official" LS1/LSx/5.3/6.0 tech thread

Mehhh... That's leaving it to chance. I'd rather know WHY I should swap it out, as the kid explained. :flipoff2:
 
help plz - I hate to tie up Jims time for something trivial. My harness from him is so old that the markers are faded. I lost the wire that revs the motor when the OBA (old A/C Compressor) comes on. It used to work but in an old trail fix it got cut somehow. Also, is this input a 12v + input or 12v -? Seeing as all of the outputs are 12v -. motor is 6.0/ cable pull / manual trans
 
Hopefully its the same color, if not I'll pull the red plug and see what pin it is.
ai552.photobucket.com_albums_jj335_jrhxj1_Mobile_20Uploads_IMG_20150318_162255649_zpszzfzl4ox.jpg
 
The AC trigger wire on my Silverado is a light green as well, just for reference.
 
I've got a question regarding the use of an electric speedo. I noticed on the tag it mentioned "4k" as it was done by Jims performance. What speedo would work here, and fill me in on the specifics as to why.
 
I am buying a Ls motor at tax time plan buying it complete harness and ecu . It will be going in my 2005 lj and hope to use my factory 6 speed with a advance adapters plate and new aluminum radiator. My problem I need some one to do the complete swap any input for best shop around to do it would be great.
 
I've got a question regarding the use of an electric speedo. I noticed on the tag it mentioned "4k" as it was done by Jims performance. What speedo would work here, and fill me in on the specifics as to why.

what are you doing for a throttle cable?
 
what are you doing for a throttle cable?
Factory GM fits very nicely. Mines from a Tahoe. It'll go from throttle body bracket and loop all the way into into the firewall, and from there the only modification needed is to shorten the cable for the yj pedal.
 
I have an LM4/4L60 combo to swap in my '04 LJ. Since I don't have time to actually do the swap right now, I'm trying to do my due diligence on research so there will be few surprises.

One thing I haven't figured out yet is what I'll need as far as emissions/evap. The jeep has an intermittent small evap leak code now. If I will still need any of that crap that's tucked up in the passenger rear fender, I might take the time to trace the leak. If I don't keep any if that, I won't bother.

I plan to run the stock tank with the Novak pump regulator bypass, engine is a return system. I'll be running dual computers, jeep ecm for gauges and GM truck computer.

Anyone know what I need to keep?
 
I have an LM4/4L60 combo to swap in my '04 LJ. Since I don't have time to actually do the swap right now, I'm trying to do my due diligence on research so there will be few surprises.

One thing I haven't figured out yet is what I'll need as far as emissions/evap. The jeep has an intermittent small evap leak code now. If I will still need any of that crap that's tucked up in the passenger rear fender, I might take the time to trace the leak. If I don't keep any if that, I won't bother.

I plan to run the stock tank with the Novak pump regulator bypass, engine is a return system. I'll be running dual computers, jeep ecm for gauges and GM truck computer.

Anyone know what I need to keep?

i deleted evap and stuff. i capped my return and had the pooter flasher adjust the tables accordingly. ran the return from the wix on the rear rail.
 
So ill ask here first before general tech. i have a 02 5.3 out of a Tahoe. the harness that came with it is junk and cant be used. ive looked for a used harness and then having it sent off to get cut down. after talking with several friends that have had that done ive decided it may not be worth the headache (both had plugs that still needed to be extended re-pinned, and aging wire that started have problems a year or so in). so i can get a newly build harness for around 500 dollars give or take. all new wiring and plugs. The next problem ive realized is having the computer flashed, i've had some friends have problems with getting them flashed and fuel tables being screwed up and never running right. plus if i ever change cams ill be looking to have it tuned. I CANT AND DONT want to learn how to program and tune the motor. so im now looking into self-learning efi systems most are 1600+ except fitech. i realize they may not be able to do everything the 1600+ setups can do but i dont need it to really. if it can setup a good base tune and have the ability to relearn if i change the cam later on i would be happy, and at the point of a new harness and a ecu flash its only a couple hundred dollars difference in the two. so which option would you go with?
 
So ill ask here first before general tech. i have a 02 5.3 out of a Tahoe. the harness that came with it is junk and cant be used. ive looked for a used harness and then having it sent off to get cut down. after talking with several friends that have had that done ive decided it may not be worth the headache (both had plugs that still needed to be extended re-pinned, and aging wire that started have problems a year or so in). so i can get a newly build harness for around 500 dollars give or take. all new wiring and plugs. The next problem ive realized is having the computer flashed, i've had some friends have problems with getting them flashed and fuel tables being screwed up and never running right. plus if i ever change cams ill be looking to have it tuned. I CANT AND DONT want to learn how to program and tune the motor. so im now looking into self-learning efi systems most are 1600+ except fitech. i realize they may not be able to do everything the 1600+ setups can do but i dont need it to really. if it can setup a good base tune and have the ability to relearn if i change the cam later on i would be happy, and at the point of a new harness and a ecu flash its only a couple hundred dollars difference in the two. so which option would you go with?

First, disclaimer: I have no personal experience with this yet other than research and owning several ls powered vehicles, and I have an LM4/4L60e sitting on my garage floor...

What transmission? If you are using a computer controlled automatic, you're going to have to deal with factory harness and computer anyway right?

If you're using a manual or non-computer auto, and you don't already have a harness, I'd go with a standalone for self learning and overall simplicity.
 
First, disclaimer: I have no personal experience with this yet other than research and owning several ls powered vehicles.

What transmission? If you are using a computer controlled automatic, you're going to have to deal with factory harness and computer anyway right?

If you're using a manual or non-computer auto, and you don't already have a harness, I'd go with a standalone for self learning and overall simplicity.

All the self learning systems can control a computer controlled transmission from what I’ve seen


Sent from my iPhone using Tapatalk
 
It's usually cheaper to use the factory stuff. The fuel tables can't get screwed up by flashing the computer, that's strictly in the tuning.

It might cost you 350-500 bucks to get it tuned...and most people only charge you once for the initial tune and licensing the computer to their tuning software. Updates are usually free, at least from every tuner I've ever used.

A grand is a lot cheaper, right?
 
Last edited:
It's usually cheaper to use the factory stuff. The fuel tables can't get screwed up by flashing the computer, that's strictly in the tuning.

It might cost you 350-500 bucks to get it tuned...and most people only charge you once for the initial tune and licensing the computer to their tuning software. Updates are usually free, at least from every tuner I've ever used.

A grand is a lot cheaper, right?
X2. I would use factory efi and have a tuner tune the buggy, even if you end up doing it twice.
 
It's usually cheaper to use the factory stuff. The fuel tables can't get screwed up by flashing the computer, that's strictly in the tuning.

It might cost you 350-500 bucks to get it tuned...and most people only charge you once for the initial tune and licensing the computer to their tuning software. Updates are usually free, at least from every tuner I've ever used.

A grand is a lot cheaper, right?

A grand for what? The fitech system is 750 and fuel tables aren’t able to change unless you download their tuning software which is free but I’d never use since it is suppose to be self learning


Sent from my iPhone using Tapatalk
 
You said a harness for 500 and then worst case, 500 for tuning. That's a grand, right?

The capabilities of the factory ECM are awesome and parts are everywhere. I never figured out why anybody would use anything different.
 
A grand for what? The fitech system is 750 and fuel tables aren’t able to change unless you download their tuning software which is free but I’d never use since it is suppose to be self learning


Sent from my iPhone using Tapatalk

$1000 if you need trans control.
 
dude. just get a brand new wrapped harness for $500 from current performance and then get the computer flashed for $75 (includes return shipped) and be done. I thought you were doing th3500/400, but if youre switching to a 4L then simply go standalone on the trans - eliminate the computer control. not needed.
 
Back
Top