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I have a wrecked '89 K3500 with a TBI 454/Turbo 400 combination. I want to use the TBI motor in a '54 GMC 1-ton.

My first thought is to disconnect all the wires from the motor marking them as I do, and then trace each of those wires and grab the associated components, continuing to follow wires from those components and grabbing more components until nothing is left.

I swapped an old Audi (Bosch) injected motor once but have never tried an EFI swap. Is this easiler than I expect, or is there a good source of the information I'll need as I do this?

I'd never considered trying something like this until recently when my K3500 was involuntarily converted into a parts donor. At this point in the game I'd still consider converting the motor to carburated and ignoring the injection...

Your best bet is dropping it in your Sub topped with a 6-71 blower. I think thats the easiest route.

Here is a pretty good article on the subject: http://www.automedia.com/TBI_Fuel_Injection_Conversion/pht20001001fi/1

Nice link.

Thanks!

Depending on how much you want to graft over, you will want the engine bay harness and the dash harness to start with. You may want the gauges as well as electric speedo's started in the late 80's.

I have found it easier to leave the wiring on the engine and pull the harness through the cab to pull with the engine. It will be easier to remove the fenders here, however not required.

The A/C and fan control are part of the engine harness. These are not needed to make the engine run - you should leave for now until you get everything from the donor. The engine harness will go through the passenger side firewall to the ECM under the dash. There is a horse-shoe looking clip and about a pound of silicone like stuff where the wiring harness goes through the firewall. The harness then connects to the ECM, dash harness and fuse box. Remove the clip, and chunk away the silicone and you will be able to pull the connectors from the inside through.

The dash harness has the ALDL and the check engine light, and may or may not be connected to the ignition switch (vehicle dependent). I would also grab the cruise control and even the steering column personally.

The fuel pump control wire and the fuel level gauge are run together - one is pink, one is brown (dont remember which is which right now) If you do not have a good 1Bar fuel pump, then I would also grab the fuel tank and tank wiring. At that point, the lighting wiring is the only thing left from the K3500 that may be of interest. Then again, painless wiring has universal kits.

I also recommend to get a good wiring schematic of the K3500 as this will be essential for trouble shooting.

Scott

you may also want to check here

I have converted a '62 c-10 to FI. Grabbing as many of the FI parts off the doner truck is a good idea. Don't forget the air cleaner, since some late models have the MAF sensor in them nowadays. You can also convert your original fuel tank to FI if the doner truck tank doesn't fit, but using an external FI pump is not the preferred way. And there is an aftermarket electronic speed sensor so you can use your original speedo. There is an outfit in Arkansas called Street and Performance that deals exclusively with FI conversions, harnesses, etc. and are very good to deal with. When you are done, you will have a very unusal truck, since most older cars and trucks at the shows do not have FI.

Thanks guys, this information should give me a good start! I'd forgotten about the Jags that Run information. I just snagged an S-10 4x4 frame to use under one of my projects, so I need to order two of their books.

Thanks!

More information or suggestions will be welcome!

You might check with Tabdoo. He did this conversion on his truck.

I've ordered a couple of the JTR books which should help a bit.

Has anyone used the Painless harness? Is having a new harness worth $500 over adapting the stock harness from the wrecked truck?

That is amazing Scott. What a wealth of information.

I did something similar. I pulled the TPI fuel injected 350 out of my IROC. However, I elected to save $400 bucks for the Painless stand-alone wiring harness for the L98 TPI. You might contact them and see if they make something for your TBI 454.

One thing I think you'll have issues with is the width of the 454. Although I do think it will fit between the framerails, you may only have room for the stock iron exhaust manifolds. However, you'll also have to scrap the stock steering system and modify that...one of the bigger hassles of the job.

My small block swap barely has 3 inches available to the framerails for an exhaust system. 2 1/2" if I shim over the stock steering box as far as it will go. You've got lots of room on top, but severely limited on the sides.

I checked the Painless web site and they do have a harness that appears designed for my exact combination of parts. The price is closer to $500 though I didn't shop for deals, just figured I'd chase using what I have before spending the bucks.

And I noted the TPI stuff too, though I'm not ready to part out my TPI car, I hope to keep drving it a few more years.

There are several 454 powered AD trucks that show up at local shows, so I know it can be done, and I've looked pretty hard at how various details were handled. Power steering has been part of my plan for quite a while and the kits that use a 70's pickup box in front of the axle looks like my answer.

The 454 is coming out of the pickup that until recently I used to tow my trailer, and I'm pretty much satisfied with the power in its current form. I expect the completed truck to weigh about 5,000 where the donor truck was closer to 6,000, so I'll gain a little performance there. On the minus side I'm using 3.73 gears where the donor truck has 4.11, so I'm trading off leverage against weight and hope performance stays in the acceptable range.

A cam change will help greatly, even with the lower gear ratios.

I would save the $500 as the stock harness is fine if you can read a schematic.

I had a friend who used the Painless wiring harneess. I saw the instructions to it and I did not know what the heck they were abreviated and confusing. It may as well have been in Chinese. Also, it was not nicely shrink wrapped like the one I got from Street and Performance, and some of the wiring was short. Now in all fairness, that was a couple of years ago, and maybe they have come up in their quality. One thing for sure, you can't beat their price.

Steve, I can't see how your truck could possibly weigh 5000 pounds. I'm pretty sure 3/4 ton trucks were in the 3500 lb range, plus or minus a hundred.

The big block engine actually weighs pretty close to the weight of an inline stovebolt engine, so I don't see that as a source of weight gain. I can see if you converted it to 4WD, but I would think that would still only tip the scales at 4000 pounds or a little over.

So I would imagine that EVEN with your switch to taller 3.73 gears, you will have FAR more performance than your old truck had, because of a ton less weight.

A '54 Chevy 1-ton cab and chassis (3803) weighs 3,620 at the curb according to the resto pack. That's a bare frame behind the cab and without any options. The utility bed I'm planning to use weighs more than 1,000 pounds, and may be closer to 1,500.

I'll likely weigh the truck when its finished, but I'll be real surprised if it comes in under 5,000.

If I converted to four-wheel-drive at this point I'd do so by mounting the cab on my K3500 chassis, that with the original cab and box does weigh 5,700 according to the reference I've used.

Its possible with that heavy bed I won't weigh any less than the donor truck. The trade offs of heavier steel in the cab, but less cab, less upholstery and sound deadening, but more bed, seem to me to mean it will weigh less than the donor truck, but not less than the stock '54 GMC.

I installed a 454 in my 1986 C20 and also installed a TBI from a 91 suburban along with dual GM in-tank full pumps from a 1990 C30 It turned out Awesome !! It's not as hard as you think but if you have any questions get ahold of Affordable fuel injection Their the best when it comes to GM injection. You can get any Info/ parts/wiring harness/ custom ECM chips... you name it (ask for Mark)
I was so happy with the way my 86 turned out that I ordered a TBI kit from them and installed it on my 51 and im even more pleased with it... the wiring turned out nice and it Fired right up on the first crank
I think TBI is the only way to go
Good luck and post some pictures of the install
Todd