S10 Swap how to

[skymangs]

I almost forgot. Somewhere near the beginning of this thread, I was asked to discuss wiring harness options. Basically there are 3 in my book.

1. If you are retaining the S10 4.3L with TBI, I use the stock S10 harness and ECM. Be sure you label everything before you unplug it if you aren't familiar enough with the harness to recognize the connectors.

IMPORTANT! BE SURE YOU ARE USING A KNOWN SYSTEM! In other words, before you dis-mantle the S10, be sure to drive it and identify, diagnose, and repair any electrical issues prior to the swap. Diagnosing electrical gremlins on a harness after it's been apart and flexed, and moved around and re-connected is NO FUN!

Using the S10 harness is pretty straight forward. I mount the ECM behind the glove box (above the stock heater box). I run the ECM harness though the firewall on the right side of the engine. All the engine connectors will be re-used. The wiper plug can be removed, delete all the wires but the switched power, then lengthen it to run it into the cab. I've built 4.3L trucks that still have the factory ABS and cruise control even (note: to have the cruise control function, you need the S10 brake light switch).

I also delete the courtesy lights (under dash) and remove the stupid key in/lights on buzzer. The dash cluster plug is a pain, but pin-outs are available on the internet. See attached Pin-out for 83-93 S10's. Obviously the oil, temp, and voltmeter wires are the sending unit wires for aftermarket gauges, the left/right turn, bright ind. and SES wires must be hooked to individual lamps, etc. If you do not have basic wiring proficiency, do not attempt this! get professional help.

[skymangs]

Option 2: If you are going the small block route. I WILL not build a truck without a new body harness. I've seen way to many engine fires from hacked up, worn out, corroded connections, re-purposed harnesses!

One harness I prefer to use for a basic truck is the EZ wiring 12 circuit mini fuse harness. For the cost, you can't get a better harness. If you plan on power seats, windows, locks, door poppers, etc. then the 21 circuit harness is for you. Installing a full harness is not for the faint of heart. It takes me 10-14 hours for a harness install, and I do them all the time. Do not cut corners, solder/heat shrink all your connections. Also, be sure you use the worksheet if you decide to re-purpose any of the circuits. It will save you lots of headache if you ever need to diagnose an issue later.

I start by laying the harness out on the bench and going through it wire by wire. Deleting wires I won't be using (i.e. temp/oil sender wires if I'm using mechanical gauges) and accounting for every accessory BEFORE I try to install it. I also use this as an opportunity to re-route any wires (dome light power from taillight section to dash section, etc.) Once that's done, I zip tie my 4 basic sections together. Engine, Headlight, taillight, and dash. Then I begin routing each group. I work one section at a time, starting with the dash section (specifically ignition switch), when that section is done, I move on to the next.

[skymangs]

Option 3: LS1 builds, you have the most fun ahead of you! Not only do you need to re-work the stock driveline harness to stand-alone, but you will also need a new 12 circuit body harness!

If you are looking for detailed information on LS1 pin-outs, harnesses, etc. the site for you is LT1swap.com No one has a more detailed instruction manual for these. You can also send your PCM to him for programming. He does an outstanding job.

Be prepared for tedious work. An LS1 harness takes me about 15 hours to re-work. I hide all the wires under the intake to keep the motor looking as clean as possible.

[HUSSEY]

Awesome post!

I'd like to share the mount design and dimensions I came up with. I put these together with advice I got from other builders on this forum (jeffs51chevy, av8tr33337 aka Bartman, 99toLife, and Skymangs) They're made primarily from 4x4 in. 11 GA tubing.

The front mount is placed 2 in. behind the oval hole on the frame, I can thank Bartman for that: https://www.youtube.com/watch?v=cdgYy5YtW8k.

The center to center distance between the front and rear mounts on mine is 36-1/4 in.

I'm running 2 in. drop spindles on the front and 2 in. drop blocks in the back (started with 3 in. blocks but ended up with 2 in. blocks). That puts my running boards nearly level with a slight rake, about 1/2 in. to the rear. The front bumper sits 5-1/2 in. from the ground. Having driven it around I think that it is as low as I would want to go with a static drop.

With these swaps, getting the cab placed properly is critical. Once you know you've got the cab where you want it, getting the front clip, bed, and running boards in place is easy since they are placed off the cab.

There is no need to shell out $1,000+ for a conversion kit that really doesn't get you that far when this will get you the same distance for $100 or so in materials.





Downloadable PDFs which are a bit clearer are available at the following links:

https://drive.google.com/file/d/0B29...ew?usp=sharing

https://drive.google.com/file/d/0B29...ew?usp=sharing









From the top of the frame to the bottom of the cab floor support measures 4 in.





I ran an 11 GA 2x1 rectangular tubing between the two rear cab mounts and bolted to the bottom of the floor.











Of course more pics are in my build thread: http://67-72chevytrucks.com/vboard/s...d.php?t=664837

[skymangs]

Thank you.

Best pics I have off the cuff like that. The mounts are tacked on, but in the correct place. I run a bead along the top of the frame (side to side), top of the frame (front to back) on the inner lip, and vertically on the frame (top to bottom). Total of 5 beads per mount. Should be plenty strong!

[28TudorAZ]

Originally Posted by HUSSEY

I'd like to share the mount design and dimensions I came up with. I put these together with advice I got from other builders on this forum (jeffs51chevy, av8tr33337 aka Bartman, 99toLife, and Skymangs) They're made primarily from 4x4 in. 11 GA tubing.

The front mount is placed 2 in. behind the oval hole on the frame, I can thank Bartman for that: https://www.youtube.com/watch?v=cdgYy5YtW8k.

Thanks for this. I used your mount design on my build and location of the front mounts. The height would have been the most difficult to figure out so this saved me lots of time. Then I used a wood template to place the rears. Only difference is I am going to use angle iron for the backside of the mount so I can run things on top of the frame.

[User Error]

Originally Posted by skymangs

I also delete the courtesy lights (under dash) and remove the stupid key in/lights on buzzer. The dash cluster plug is a pain, but pin-outs are available on the internet. See attached Pin-out for 83-93 S10's. Obviously the oil, temp, and voltmeter wires are the sending unit wires for aftermarket gauges, the left/right turn, bright ind. and SES wires must be hooked to individual lamps, etc. If you do not have basic wiring proficiency, do not attempt this! get professional help.

I'm a bit confused... I'm going to be adding Dolphin Gauges to my 50 here soon... I'd like to use as much of the stock harness as possible... So from your post if I'm reading right you can just hook up the oil, temp, and volt wires directly to aftermarket gauges and use the oem Senders? (mine OEM senders are currently out and laying on the intake causing some ECM/TBI issues Manual senders are in the oil and temp locations) (Fixing someone elses build that's how they left it) Also can you cover a little about the Fuel and Speedo senders vs oem wiring or rewiring? Thanks... you're a ton of help man... I so wish you were closer I'd get you to build me a couple more trucks...