350 TBI PCM questions

[Olson64]

Hey guys! I have a 93 GMC C1500 with the 4.3 TBI and a 4l60e. I recently found a fellow who has a 92 chev k2500 with a 350 TBI and I believe that means it has a 4l80e. Anyways, he wants to sell it, and I’m debating about buying it and I’d have the engine and all the incidental pieces to do the 350 TBI swap (plus it has bucket seats, tilt column, power windows etc.). My question is, will the pcm in the truck with the 350/4l80e work in my truck with the 4l60e after the swap? Or can I reuse the pcm from my 4.3 and just use the chip out of the 350 pcm and will my 4l60e still function properly?

 

[df2x4]

My question is, will the pcm in the truck with the 350/4l80e work in my truck with the 4l60e after the swap?

Nope. 4L60E/4L80E programming is different.

Or can I reuse the pcm from my 4.3 and just use the chip out of the 350 pcm and will my 4l60e still function properly?

Once again, I really doubt it. I'm not sure how the older TBI PCMs handle things like this, but I do know that the 4L60E and 4L80E require different PCM programming to function properly.

To the best of my knowledge the only way to make this work would be to find a PCM from a truck with the exact same options as what you're trying to install, or have one of your PCMs reprogrammed for that combo.

If you go ahead and swap the 4L80E in as well then the PCM from that truck might work, provided that everything else is also the same. If you have it anyway I'd at least consider this option, 4L60Es are pretty weak.

 

[Olson64]

Brought the 92 k2500 home tonight and put her on the lift, it appears to have a t.v cable so I think that means it’s a 700r4? It’s definitely not a 4l80. So I think when I do the swap I’ll be able to use the 5.7/700r4 in place of my 4.3/4l60e. And since I have the whole truck I have the pcm and harness if it’s different?

 

[Erik the Awful]

It's a "4L60", nee 700R4. 1993 was the swapover year to the 4L60Es.

 

[bobbyt]

Nope. 4L60E/4L80E programming is different.



Once again, I really doubt it. I'm not sure how the older TBI PCMs handle things like this, but I do know that the 4L60E and 4L80E require different PCM programming to function properly.

To the best of my knowledge the only way to make this work would be to find a PCM from a truck with the exact same options as what you're trying to install, or have one of your PCMs reprogrammed for that combo.

If you go ahead and swap the 4L80E in as well then the PCM from that truck might work, provided that everything else is also the same. If you have it anyway I'd at least consider this option, 4L60Es are pretty weak.

I'm glad this is being discussed because I've got a ? I'm new to the EFI game I'm an old school carb guy, but I do have a 92 chevy 350 tbi motor an I'm swapping the intake/ fuelpump out for a 4barrel an a MSD arttomic 2 efi an my ? Is what do I do with all my other wiring, an can I just take my old computer that runs the truck out an do away with it??? Plz someone chime in an let me know because I'm gonna have a new msd ignition box an distributor running the ignition an the msd atomic 2 has its own internal computer?? So plz inform me if u have experienced this before an thanks in advance, an my truck is pre 4l60 an 4l80 it' still have the 700r4 so no computer needed for that

 

[Erik the Awful]

I have a Holley Sniper on my '89. The computer is still in place because it controls torque converter clutch lockup - which still works just fine with no TBI.

 

[someotherguy]

Brought the 92 k2500 home tonight and put her on the lift, it appears to have a t.v cable so I think that means it’s a 700r4? It’s definitely not a 4l80. So I think when I do the swap I’ll be able to use the 5.7/700r4 in place of my 4.3/4l60e. And since I have the whole truck I have the pcm and harness if it’s different?

"6 lug" K2500? Then yes it's a 700R4/4L60 (same trans different name.) Had to be an 8 lug to get the 4L80E.

Richard