'87 to '78 Interchangeablility?

[Russ130]

I just picked up an '87 parts truck for the bed. I am planning on swiping the A/C as well. Will the TBI swap over to my 383? The '87 has a 350 that runs really well. Since I'll have both beds off the tanks would be real easy to get to. How about the steering column? Any other ideas? Thanks.

[Blazin]

For the TBI you will need the heads off the 87 motor onto your 383.
If your 78 is an AC truck it shouldn't be to much of a hassle. If yours is not then you will need to cut out some of your firewall, maybe weld some of the old hole closed to fit the AC box, plus you will have to mount all the ducting under your dash, also have to run all the vacuum lines, swap over the heater control, and swap the glove box tray over.
As far as the steering column you will need to splice in some of the wire harness in order for the high low beam, windshield wiper switch etc. to work. You will need to delete the wiring from the old wiper switch, and floor mounted high beam.
As far as the bed as long as the gas filler is on the correct side that should mount with no major issues. The tail light plug from the bed to the frame is round on the 78, and square on the 87. You will need to cut one or the other of the pig tails off and splice it on.

[Russ130]

Luckily my truck was A/C equipped but everything has been removed. The glove box on mine has trouble with opening and staying closed so I'm glad you mentioned that. The bed is the reason I got this truck and will be replacing a '81 up bed so the tank has already been swapped over to the drivers side. I have aluminum heads on my motor and swapping over to factory is not going to happen. I was wondering if there isn't a intake that would fit my older block and let the TBI unit bolt on.

[Captkaos]

There should be an aftermarket intake that will put a TBI on a pre 87 block.
you will need a chip for the TBI to work on the 383 efficiently, but it doable.

[Blazin]

Wasn't sure about the intake. I would have thought there was one available but I have never seen one personally.

[Russ130]

Well here are some pics of the soon to parted out truck. I was talking to a friend of mine and he also brought up the fact that the wiring harness is different and even uses different fuses. So maybe the TBI swap won't happen anytime soon. Capt. where and what chip would I get for the 383?

[Russ130]

And a couple more...

[Captkaos]

Everything including the wiring harness will swap over to the other cab.  You could pull the whole thing out (wiring and EFI ) and put in in the donor if the donor runs.
TBI Chips can make you a chip for it.

BTW, this is getting REALLY close to a For Sale post which requires Site Supporter.

[Russ130]

Yes I understand it is real close but I have to be honest with you I already have everything listed on craigslist. I posted these pics so people can be refreshed as to what we are talking about here. Since mine is a chevy and this is a gmc somethings won't interchange like grill and tailgate. To my knowledge there is no other part that won't swap because of make but alas that is why the post is here and the pics. To tap from the wealth of knowledge on this site. Personally I am thinking of supporting this site not so I can sell but just to help keep it going because of the vast amount of information contained here. But anyhow you have my word nothing is for sale on this site however I am willing to help people out with free stuff from the '87. Basically anything that will be going to the scrapyard. Obviously the bigger parts are not going to the scrapyard and are not free. But say someone wants a gas pedal or a A/C control panel or that type of thing I would be willing to ship those out collect for no fee what so ever. The cab and frame are going to the scrapyard so if anybody wants something off of them let me know. Minus the speedo cable, seatbelts, trim for the headliner, radio, glove box and calipers everything is junk to me, that includes the gauge cluster and bezel the metal dash frame that is uncut.

Capt. - there was a guy on here that needed a new dash frame but I can't find his post to offer it to him. You might remember he wants to relocate the radio to where the heater controls are. If you can find him can you please extend my offer to him and since that dash was such a mess I'd like to see him get the mint condition bezel as well. On another note I am going to pull out the complete harness along with all the sensors, gas tank and ECM. I'd like to get a programmable chip if such a thing is made because the 383 is built for torque not horsepower so an off the shelf oneprobably won't work to its highest potential. Of course I understand it will work just fine.

[Russ130]

Well a little has changed since my last post here. I'm not going to be swapping over to TBI because there is no way I'm going to give up horsepower for less warm up time. I have found out that the ECM will never be capable of running my 383 anywhere near as good as it runs right now. I have also found out that since I have gear drive the knock sensor will always think the engine is knocking. So what a waste of time I pulled out the entire wiring harness without cutting a single wire for nothing. I'm still going to keep the tank but the pump and sending unit will be gone. Well at least I'll still have the A/C to add to my truck. The metal dash part that everything mounts to cannot be removed by just unbolting so that is going to the scrapyard. Everything else is still as planned.

[Captkaos]

Who told you it would never run as good as it does now?
The gear drive will cause the ECM fits, but that can be bypassed.

[Russ130]

I actually got that from a site that sells TBI chips and other TBI related stuff.