The Stovebolt Site Forums The Shop Area The HiPo Shop 5.3 swap wiring question

I am putting an 06 5.3 in a 53' pickup. I was wondering if I have the computer reprogrammed, can I use the original harness w/o modifying it, if the length works out for me? Can I just plug everything back in where it goes, even to sensors I may not be using. If programmed to not use whatever it may be does the computer not recognize those things and just be used to terminate the wire connection. I plan to use the escalade cover so everything should be covered and not seen. Thanks for any input!

I have a 2007 6.0 in my 1952 3100 and asked the same question you did here.After talking with Mark at Street and performance 479-394-5711 http://www.hotrodlane.cc/.
He said it can be done but would require a lot of time and you need to know what you are doing.I wanted a very drivable zero problem and reliable truck anyone could drive.So I went with there harness and they reprogrammed the computer also.The wire harness Install was very easy and worked with no problems.

Thank you sir! I have found that in my quest to complete this thing that I am having loose the tight wad part of me that still resurfaces occasionally! I to want a problem free driver. Started out thinking I would stay original when I started but have learned so much since the purchase, ie the torque tube for one! But I have decided I'll be happier with something that I can drive anywhere. Was wondering if u had power steering and did u have to notch the crossmember to clear it, assuming u have a mustang II? I purchased one from speedway and don't see any way around it because of the design and not improer installation(wAs installed by local rod shop)? Thanks again! Have u got any build or I guess any pics of the 3100?

"U" will get a lot more responses if "u" don't use text message grammar and spelling. Most of us oldtimers here appreciate being able to read full sentences without having to guess about the latest shorcuts to polite conversation!
Jerry

Websterhotrods...+1

Grunt
I only have a few pictures of the truck it was built before being a member here and photobucket.
http://s897.photobucket.com/albums/ac176/webstershotrods/
The suspension is corvette front and rear ,steering is rack and pinion Thunderbird .I bought the X member and sub-frame's to do this from
http://www.progressiveautomotive.com/
Talk to Bob there 740-862-4696.
If I were do build it again I would use a 100% new frame from progressive or Art Morrison MAXG http://artmorrison.com/maxg.php

"Modifying" the original harness really means removing the wires that are not needed anymore. So really, you could just cut off yourself the wires you do not need for your truck. Of course, be careful cutting the correct ones!... It really helps to have the wiring diagram...
When I did my LS engine swap (not in a Stovebolt), Speartech (www.speartech.com) reprogramed my computer and removed the unneeded wires from my harness: what is great is that they then tested my modified harness together with my reprogramed computer before shipping everything back to me: great for peace of mind!
That way, you know it works.
Or they can make a harness for you, allowing you to place the computer wherever you want.

I am also in the planning stages of converting my 216 to a 4.3 v6
TBI (throttle body injection)
In my case I am using a 1991 Astro as the donor vehicle. All the wiring stuff from the original engine has been removed and the v6 engine is in place as well as the original computer. I contacted Painless Wiring & they sold me a harness built for this engine and computer. They gave me the service code which is a sticker on the face of the computer and it matched. I will be hiring a guy who has a lot more experience and knowhow to help me do the install. The nice thing about it is the all the connections are labelled. I am wondering why someone, who wants to do this would have to re-program their original computer to make the swap? Or will I also have to re-program????
Hopefully someone who has done this before can shed some light on this question?

You will have check engine lights or codes from the sensors not being used .When the computer is reprogrammed they remove that and should retune the engine for you.I would ask Mark at Street And Performance 479-394-5711
http://www.hotrodlane.cc/

For a TBI conversion, you do not have to reprogram the computer but it is highly recommended that you change the chip in the computer, to take into account the sensors you do not use, and maybe also fine-tune the engine to the kind of use the truck will see (race, cruise, economy...). Howell is a place that sells custom-programmed chips.
For an LS engine conversion, you cannot change a chip, you have to have the computer reprogrammed, one of the main reason being the built-in anti-theft system that has to be removed or your conversion will refuse to start (I think it is called VATS).

For anyone that wants to try to do these themselves it's not so hard if you start with a "LS series" engine truck harness.

For the most part the engine harness is a standalone harness already. If you use the truck under hood fuse block you just have to hook up one power wire, one ground wire, and one ignition wire.

You would still have to get the computer changed for anything you aren't going to use from the original truck.

A great website for information on swapping in the “LS series” engine is LS1tech.com.

Here is one specifically on harnesses: Removing extra wires from a 99' LS1 harness.

On that website there is a section devoted to Conversions & Hybrids. At the top of the section are several very good stickies. The most useful I think is LSX Swap FAQ and Hall of Fame Threads

I myself haven’t done any swaps but I have helped a few of my friends do them in their cars. I figure it’s good to get some practice in before I make the mistakes on my truck

Sorry for posting links to another forum, but right now that is THE source for “LS series” engine swaps.

Here is the thread I couldn't find yesterday:

LS1 harness: Start to finish

Several other wiring and swap posts.

I have done some research and found out from GM that my 91 Astro donor 4.3 v6 did not have vat (vehicle anti theft) installed, so I think I'm good to go, they said it should start ok. The earlier TBI engines didn't have them. I'm not sure what sensors I will not reconnect. I think I need all of them.
Only time will tell. Once the install is done I'll know more. Always open to comments of people who have experience doing this.

Vickraft,

http://www.ifsja.org/forums/vb/showthread.php?t=69362

http://www.binderplanet.com/forums/showthread.php?t=47254

http://www.bigscaryjeep.com/TBI_FAQ.html

http://www.megamanual.com/ms2/GM_7pinHEI.htm

http://www.megamanual.com/ms2/GM_7pinHEI.htm

http://www.jagsthatrun.com/V8-chapters/V8-tpi-Speed-Sensors.pdf

These are some of the site I have read before starting the swap from carb to TBI on the 250ci engine in my Suburban. A lot of good info, I would say read it all before you start! The page hosted on BinderPlanet has many links you need to open to find more; even the Megasquirt site has nice info, to better understand what needs to be done.
I have also bought a custom chip from Howell.
The main issue is that I cannot get my truck to idle properly, and I have spent a lot of time troubleshooting!...
Good luck!

Again I have to say, thanks very much, to the people who give their time and consideration from their busy schedule and help me with some very useful reading and advise.

Here are the things that I know so far.
I am using the exact same computer,engine,transmission&steering column from the donor vehicle. In this case 1991 Astro with no VAT
The only change will be, that instead of using the original harness I have a Painless kit made for the service number that appears on the original computer. All connections are labelled. Absolutely no modifications to anything else. Its almost like its still in the astro and I'm just changing replacing the harness.
I have decided to hire a profesional GM Tech person to help me.
Hope to work things out with him, or maybe just watch & learn. I will give an update on my progress later.
Thanks again.