51 GMC 5 window+S10+5.3/4l60E

[wedjim]

Engine bay pic of my 49 project nearing completion.



Wife just transferred money for driveshaft and exhaust today!

[99 to Life]

Looks great man, does it have the original harness reworked or an aftermarket?

[wedjim]

Thanks. I use a new harness from EZ Wiring for the truck, I had an engine harness modified by someone I found on Ebay, along with a PCM from spare ECM, also on ebay.

It uses the drive by wire pedal and all also, pretty happy with it so far.

[99 to Life]

So you are using EZ plus the original harness? Not quite following you, sorry.

[wedjim]

No problem. I purchased the truck with zero wiring left in it, other then some stragglers left on the headlamps and their rusty buckets. So I wired the entire truck with an 18 circuit EZ Wiring kit. They have labeled every wire individually every 12 inches or so and it was the easiest part of the build.
The engine harness taps into it in a couple spots for battery power and ignition. All that you have to do on your own is grounds, which is fairly easy for each light and a few dash commons to accomplish.

If you have any questions i'll help if I can. Doing stuff this for a living makes it seem less daunting to me maybe, but really anyone with some courage and some basic hand tools can accomplish it.

[99 to Life]

wedjim, ok I got you. I too used an EZ 21 circuit, but I'm just running carburation and hei. With any fuel injected stuff, I'm not very exposed to it, so I don't understand it all that much. There just seems to be sensors for everything. So I'm assuming the ECM was modified correct? That is the stuff that boggles my mind, needing to know all the stuff you need to bypass, like VATS and start in any gear and all that stuff. It would be great to have a detailed list on how to do a swap like this, wiring the EZ was pretty easy. Im just confused on all the stuff the the newer engines need. I've envisioned a swap like this for a 53' belair, be a family car cause I want no fumes in there. But just been overwhelmed as I usually hear a harness mod is 6-800 bucks. I'd just like to know more about what the engine needs as far as power and sensors and how to simplify it. Lastly I'm assuming you have to have an EVAP system in working order too right. thanks man.

[wedjim]

Ok, cool so if you have the main wiring done the addition of the modern running gear is pretty straight forward. It might look daunting, but it isn't really bad at all. The PCM can be programmed to eliminate vats and(for offroad use...lol) to eliminate the rear O2 sensors, Evap system, EGR if needed and also engine mods, although mine is stock other then some headers and air intake since i'll be driving it often.

I mounted my PCM under the left headlamp on a fabricated bracket, it is a matching PCM for the engine/trans combination. The harness mods were basically only to eliminate circuits that wouldn't be needed, like the large fuse box and relay box attached from the factory. If you have a big garage floor to work with you unwrap the harness and remove the components and wiring that isn't needed to clean things up a bit. Rewrap it afterwards, leaving wiring end to attach for ignition feed, battery feed, grounds, speedo output, etc. There are several youtube vids on the process.
I was lucky to find one on Ebay for less then $400 harness included, so I avoided doing it myself, although I have in the past and it isn't a big deal. Finding a good harness for $400 was harder in my case for some reason, lol.

[99 to Life]

wedjim, great to know man. I been seeing some LS engines pop up at some salvage yards. Seems like an engine for 100k or less I could get for 800 bucks. Would it be advisable to snag a trans at the same time, those are another 800. Are there any heads up with matching trans and engine, dealing with all the bypass stuff? thanks for the heads up, seems a bit more feasible now.

[bsccp]

wedjim engine bay looking very good. Have a couple of questions: firewall is aluminum sheet? Does it seem to stiffen up the firewall to compensate for the brake and booster?
It looks like a cable drive windshield wiper setup. If it is how do you like it? Is it a 2 speed and/or intermittent?
I actually have two wiring looms. One from the '03 Tahoe for the 5.3 and the complete loom/PCM/cruise, etc from the '03 2500HD/6.0. Both are green/blue. I'm going to go with the http://www.lt1swap.com/ wedsite and have him reflash my PCM to elimate the VATS, etc. I figure between the two of them I can get at least one right!
Finally getting to the cab corners. Floor is marginal but I plan to replace the rear floor with 18ga with supports and some bead rolls.
Overlooked a spot on the lower latch side of the driver's side door. Passenger side was fine. Just shows how the difference in moisture, dirt,etc from side to side. Oh well just cut off the lower 4" and replace with a patch panel. I dont't have a shrinker/bender so have to go commercial. Rocker is pitted but solid above the brace. Plug welding into thinned out sheet metal is a little iffy but primer makes it look better. On to the front cowl and front floor boards next.
In my part of the world (West TX) 5.3's, long block without accesories go for 400-500. Complete with wiring and accessories 700-800. The thing about the 4L60E's is that they are good for about 150K before things go wrong (sun gear, etc). Finding one for a core at $150 and then having a good local shop go through it and upgrade it with a Beast sungear, 'vette servo, etc for around $800 is money well spent! Ask why I know 4L80E's are a totally different beast!

[wedjim]

Originally Posted by bsccp

wedjim engine bay looking very good. Have a couple of questions: firewall is aluminum sheet? Does it seem to stiffen up the firewall to compensate for the brake and booster?
It looks like a cable drive windshield wiper setup. If it is how do you like it? Is it a 2 speed and/or intermittent?
I actually have two wiring looms. One from the '03 Tahoe for the 5.3 and the complete loom/PCM/cruise, etc from the '03 2500HD/6.0. Both are green/blue. I'm going to go with the http://www.lt1swap.com/ wedsite and have him reflash my PCM to elimate the VATS, etc. I figure between the two of them I can get at least one right!

I used the aluminum for cosmetics, to cover tons of holes I wouldn't need. The brake booster is braced inside by the S10 pedal bracket/booster mounts that the donor truck gave up for the chassis and misc components. I fab'd it in, actually re-fabed I should say, since it was poorly done by the seller.
The wiper set up works well, 2 speed and int. I would have gone with the electric conversion which replaces the stock vacuum motor if the stock set up wasn't butchered by the seller already also. This set up is pretty easy to install though and frees up room under the small dash area if you will use A/C and other goodies in there.
Sounds like your in good shape with this wiring looms you have. I found some but sellers wanted $400-600 before being modded. The one I used was less money and already modified sold on ebay. But it took 6 weeks to get, well done though.

I did get my brake parts to replace the rusted and stripped calipers that were on the truck when I bought it, as well as the metal to metal rear brakes it had.
The driveshaft should be done today also! May be driveable and needing only exhaust by the end of this week! WooooHooo!