96 K1500 swap engine

John Lawrence Kamalani · December 15, 2021

I have a 1996 K1500 with a 350 engine and the engine is toast. My question is I also have a 1997 k3500 with a 454. Can I do an engine swap and put the big block in my k1500. The problem is, will the wiring harness from the 1997 k3500 plug into my firewall on my k1500 as the wiring is different and will it work? What else will I have to do? Anything would be helpful.

CamGTP · December 15, 2021

I mean you probably could fit it but you'd have to make a lot of custom stuff. Like motor mounts are probably different too.

The 350 computer won't run it but then if you tried to use the 454 computer it wouldn't work with the 4L60e transmission. Plus that 4L60e transmission will just grenade with the power that 454 can make. Then there are things like flex plate, torque converter stuff that would be different.

Much easier and cheaper to find another Vortec 350 engine from 1996+ that will be plug and play.

Jglew82 · December 16, 2021

What Cam said, in addition, you could do the swap if you do the whole powertrain - engine, trans, Tcase, PCM, Wiring harness, etc.

John Lawrence Kamalani · December 16, 2021

I have another engine, but I want the big block. The computers are the same as I know because I switched them one time. I also have every thing from the 97 so I'm gonna try it and see how it goes. Remember it's a Chevy. I just was wondering if anybody tried it before.

CamGTP · December 16, 2021

The computers may look the same but they still aren't the same. The calibration inside the computer is not even close between a Vortec 350 and a 7.4 454 engine. I would not run a 454 engine on a 350 calibration file.

I've been tuning vehicles for over 10 years now, seen things go downhill when the wrong stuff is used.

John Lawrence Kamalani · December 17, 2021

Thank You for the feedback. I've been working on cars and trucks for over 40 years. It does work and I have everything from the one ton truck to go on the half ton truck. I also have two jeeps and ones a V8 and the other a six cylinder and I've switched the brains on them also and the engine can't tell the difference, is because there is no difference. I have eight Chevy trucks of various years. Here are some pictures of my shop and what I do. I'd like to see your shop and by the way I'm lucky to live on Hawaii Island.

Thank You, Cameron