Painless Wiring Harness

[Jimmy P]

Since my truck is being torn right apart and I have a huge cluster*** of wires in my cab Ive been wondering if it would be better to get a complete painless wiring harness. Seems like it would make it alot easier and cleaner to put back together.

Also would this make the installation of the LS1 any easier? What about the HVAC system?

[LS6TT]

I helped a buddy install a ls1 into a old truck...anyway..we used the painless kit..HOLY crap it was great..we stripped all the wiring and interior out..used the gauges from the camaro..and made the dash...

i would strongly suggest it

[SLMDLT1]

Don't waste your money. If you have any electrical ability and some time you can make it yourself and it will be easier. My LT1 swap with my own wiring has been easier than my buddies LS1 swap with the painless. The painless left out an oil pressure sending unit gauge, so we had to make one and splice it into the computer and the gauge pigtail.

It is really easy to use the stock harness if you understand some basics of EFI wiring.

[Jimmy P]

Originally posted by SLMDLT1
Don't waste your money. If you have any electrical ability and some time you can make it yourself and it will be easier. My LT1 swap with my own wiring has been easier than my buddies LS1 swap with the painless. The painless left out an oil pressure sending unit gauge, so we had to make one and splice it into the computer and the gauge pigtail.

It is really easy to use the stock harness if you understand some basics of EFI wiring.

yea i know you said the painless LS1 harness wasnt worth it but Im talking about their universal harness that wires up the whole car.

[Physh1]

I've done a few 12 circuits and a few 18 circuits....I liked them. The first time it took a while to lay it out and figure what was going on but after that it was pretty good. I'd do it again in a heartbeat.

Cameron

[Jimmy P]

Originally posted by Physh1
I've done a few 12 circuits and a few 18 circuits....I liked them. The first time it took a while to lay it out and figure what was going on but after that it was pretty good. I'd do it again in a heartbeat.

Cameron

how do they go through the firewall ? Is there a plug or do you have to run them all through a hole? What about gauges...are they all set up for when I run my autometers?

[Physh1]

Autometers will hook up. There is a large firewall grommet with the kit so you can pull them through the firewall.

Cameron

[AntiBling]

There are also a few other companies that have popped up I have seen in my classic trucks magazine. Sell a 18 circuit kit for 165, same thing as painless being labelled on the wire every 4 or 5 inches. You can get the kits in color coded or all black if you want the sleek look.

[Jimmy P]

Originally posted by AntiBling
There are also a few other companies that have popped up I have seen in my classic trucks magazine. Sell a 18 circuit kit for 165, same thing as painless being labelled on the wire every 4 or 5 inches. You can get the kits in color coded or all black if you want the sleek look.

yea i was looking at ez wiring too.........they are $165 and from what i read on the hot rod boards they are almost the exact same harness as painless.

[Tahoekid]

I have heard on several occasions that painless is nothing but a pain.

Chris.

[Physh1]

Originally posted by Tahoekid
I have heard on several occasions that painless is nothing but a pain.

Chris. I've only heard that from people who A) have never done any wiring from scratch before and B) people who don't know what they are doing. That goes for all harnesses...not just painless.

Cameron

[dapolice1]

Originally posted by jimmy p
yea i know you said the painless LS1 harness wasnt worth it but Im talking about their universal harness that wires up the whole car.
Jimmy as you know I am doing the LS1 swap and have helped 3 other guys with LS1 swaps. I will tell you this DO NOT BUY THE PAINLESS LS1 HARNESS. Buy the Street and Performance or the Centec wiring kit. I like the Centec cause they can build you a harness for the vehicle and one for the LS1 and make them to where they will attach together.

I know you know this, but there are 2 general harnesses in the LS1 swap the engine control or LS1 harness which is a stand alone harness and the Body harness which controls the the lights etc.

Theoretically they should be able to operate independently of each other (if you don't want gauges). That is what confuses most ppl is the merging of the engine harness to feed the gauges in the body harness. No big to me and some of the other guys cause we have a deep understanding of the wiring and what needs to be connected to what to function.

I would tell you this. Contact Street and Performance and order their LS1 instructional video. They walk you through almost every aspect of the LS1 swap and even show it in several vehicles lik thier 98 OBS. It is like $20 but well worth the cash. They tell you what goes where and where you can tap for sensors vacume etc. Their harness is not cheap but I think it is the best. If you get their air intake and Air temp sensor will screw into their air cleaner. Their harness also cuts down on connects. They run wires to each individual coil instead of a junction then to the coils. It will allow trouble shooting a bad coil easier.

http://www.hotrodlane.cc/

[Jimmy P]

Originally posted by dapolice1
Jimmy as you know I am doing the LS1 swap and have helped 3 other guys with LS1 swaps. I will tell you this DO NOT BUY THE PAINLESS LS1 HARNESS. Buy the Street and Performance or the Centec wiring kit. I like the Centec cause they can build you a harness for the vehicle and one for the LS1 and make them to where they will attach together.

I know you know this, but there are 2 general harnesses in the LS1 swap the engine control or LS1 harness which is a stand alone harness and the Body harness which controls the the lights etc.

Theoretically they should be able to operate independently of each other (if you don't want gauges). That is what confuses most ppl is the merging of the engine harness to feed the gauges in the body harness. No big to me and some of the other guys cause we have a deep understanding of the wiring and what needs to be connected to what to function.

I would tell you this. Contact Street and Performance and order their LS1 instructional video. They walk you through almost every aspect of the LS1 swap and even show it in several vehicles lik thier 98 OBS. It is like $20 but well worth the cash. They tell you what goes where and where you can tap for sensors vacume etc. Their harness is not cheap but I think it is the best. If you get their air intake and Air temp sensor will screw into their air cleaner. Their harness also cuts down on connects. They run wires to each individual coil instead of a junction then to the coils. It will allow trouble shooting a bad coil easier.

http://www.hotrodlane.cc/


thanks ...i think i will order that video up. I hope once I get the ls1 bolted in I should be able to get a better understanding of it. Basically there is the ls1 harness that hooks up to the engine and the computer and then the body harness for lights and stuff. Then there are wires that come from the engine and go to the body harness for the gauges.
How much are these harnesses going to be costing me? If I could Id like to be able to use the stock harnesses and graft them together to save some money.
I hope to be getting a whole wrecked car so I can trace wires a little easier. It should also be good for stuff like the fuel pump and lines etc.....Who knows though I still have to spend my summers earnings on wheels and tires then start on the motor. God I have the longest list of stuff to get done for next summer!

[DjLunchbox]

jimmy, i ordered a LT1 harness from airdeano a week or so ago, and it should be here any day. i'll post a pic in my engine swap thread when i get it. i could have reused the stock harness, but there were too many connections that i would have to splice. i talked to dean for a long time , and he answered every single question i asked, no matter how off the wall it was. i have wiring knowlege, and now i have even more knowlege of the engine/guage wiring because of all the problems i had with my motor. bottom line, slmdLT1 is right, you can do it if you know how, and it's not that hard, just time consuming. i don't have the time or the patience to do that, so i ordered up a whole new engine harness custom cut to the legnths i need. that way it will look factory and work right the FIRST time, instead of me not knowing if a splice was bad..... :D

[SLMDLT1]

Just so ya know it took me 2 weeks working at night on my harness to get it perfect and make it look fairly stock with loom and tape. Started the first try :D

[Larry B]

What do you mean you have no patience?

[Jimmy P]

Originally posted by DjLunchbox
jimmy, i ordered a LT1 harness from airdeano a week or so ago, and it should be here any day. i'll post a pic in my engine swap thread when i get it. i could have reused the stock harness, but there were too many connections that i would have to splice. i talked to dean for a long time , and he answered every single question i asked, no matter how off the wall it was. i have wiring knowlege, and now i have even more knowlege of the engine/guage wiring because of all the problems i had with my motor. bottom line, slmdLT1 is right, you can do it if you know how, and it's not that hard, just time consuming. i don't have the time or the patience to do that, so i ordered up a whole new engine harness custom cut to the legnths i need. that way it will look factory and work right the FIRST time, instead of me not knowing if a splice was bad..... :D

well i basically have all the time in the world. The nice thing about my project truck is that I am obviosly not in a hurry on it. I still have my SS to cruise around in so its not bad. Im leaning towards the splicing but I want to do alot more research first. Depending if I do the aftermarket body wiring or wrestle with the huge mess of factory wiring I have left.

Originally posted by SLMDLT1
Just so ya know it took me 2 weeks working at night on my harness to get it perfect and make it look fairly stock with loom and tape. Started the first try :D


thats what I want to hear:devil: :D

another questions....the wire harness that goes in on the pass firewall. Most of the wires go to the computer but there are 2 or three plugs for something else. Are these for the HVAC? Does that tie into the ls1 harness or where does that go?

thanks

[dapolice1]

Jimmy, Order that video before you buy anything for the LS1 including the donor engine. They will tell you ALOT of what your asking about the swap. Their harness.. brace yourself.. is $800.. BUt look at it on the video you will see why it costs so much. EVERYTHING is outlined for you and the guess work is cut out. You will see!!!
The video will tell you what you need to look for. The fact that the 97-98 fuel rails are the easiest to use over the 99 up cause the later uses an in tank pump and regulator which can be hard to install. There is only one fuel line in 99 up and the 97-98 has regulator built on the rails. They offer diffrent fuel connectors to allow you to run braided or other line to your rails. Man the info is endless. The issues with oil pans and some will not work in some newer chassis. The camaro pan will work with our trucks the vette won't. The truck pans are cool cause they have a float in them to warn of low oil level, but I am not sure they will allow enough ground clearance for our trucks.

It is a must have BEFORE you strat buying.

[SLMDLT1]

some are gauges and some are the hvac.....you need to go down to GM and get some schematics from alldata :D

[Jimmy P]

Originally posted by SLMDLT1
some are gauges and some are the hvac.....you need to go down to GM and get some schematics from alldata :D

would these be in a haynes or chiltons manual? Where do the hvac ones run to in the engine compartment?
thanks

Originally posted by dapolice1
Jimmy, Order that video before you buy anything for the LS1 including the donor engine. They will tell you ALOT of what your asking about the swap. Their harness.. brace yourself.. is $800.. BUt look at it on the video you will see why it costs so much. EVERYTHING is outlined for you and the guess work is cut out. You will see!!!
The video will tell you what you need to look for. The fact that the 97-98 fuel rails are the easiest to use over the 99 up cause the later uses an in tank pump and regulator which can be hard to install. There is only one fuel line in 99 up and the 97-98 has regulator built on the rails. They offer diffrent fuel connectors to allow you to run braided or other line to your rails. Man the info is endless. The issues with oil pans and some will not work in some newer chassis. The camaro pan will work with our trucks the vette won't. The truck pans are cool cause they have a float in them to warn of low oil level, but I am not sure they will allow enough ground clearance for our trucks.

It is a must have BEFORE you strat buying.

kool thanks I just busted out the debit card and ordered it!

[DjLunchbox]

yeah, they should be in any of the manuals. even the chiltons crap has them...

Originally posted by Larry B
What do you mean you have no patience?

you should know after 24 years of dealing with me:D :crazy:

[SLMDLT1]

They are in there, but they are not as detailed as the alldata ones. They tell you the circuits and the locations of the wires.

[dapolice1]

Originally posted by DjLunchbox
yeah, they should be in any of the manuals. even the chiltons crap has them...


Jimmy be careful of the chiltons and haynes. Haynes tends to be alittle better in the wiring diagrams, but I have found some of the color coding is incorrect.
I guess GM tried to keep color the same through out the OBS years, but I have found odities in some areas especially in installing alarms.

I would HIghly suggest you buy the GM dealer service manual set for the years your using.

I have bought one for the 92 which is the year my truck is, but I am not using anywiring from it. I did this so I can look at the 95 harness I am going back with and see if the color coding is similar and if connectors interchange with some from the late dash. This will help me answer the questions that are always asked about the dash swaps from early OBS to Late OBS.

I bought the 95 cause that is the harness I am going back with.

I bought the 2000 cause I have the headlight harness from the 2000 escalade that I am going to hopefully be able to plug into the 95 underhood body harness, but if not I will know what needs to be spliced and where to help guys with that.

I just sent payment for the 1999 GM manuals cause they cover the OBS and mid 99 NBS change. I want to see what some of those diffrences are.

You don't need that. If you buy a body harness from Painless Or my favorite is CENTEC wiring it should be an easy install ask me and I will tell you what I can on the wiring man that is what I am here for. CENTEC has a nice panel and reletively inexpensive.

I know Cameron and the other guys will help you. That video will help you on the Engine harness wiring. It goes over their harness, but they tell you this X colored wire goes here and don't hook it there. Then they show you in depth where on the engine it plugs in. I am going to get their harness man it is alot of cash but when you see how nice it is you will know why. I have heard lots of PAINLESS LS1 harness that got thrown away and the S&P harness was used with now problems.

I also have a guy here in san antonio that is real nice and will cut me a deal on the LS1 reprogramming. I am going to run two computers. We don't currently have pipe emissions testing but it almost passed this year. So I am going to have him run me a custom tuned for the LS6 for high performance. and one for the emmissionstesting time. I am running cats and all, and I know you from up north and they have some bad Emissions laws so you might consider that.