early 4l80e to 6.0?

[joe yuhaus]

I have a 1993 k3500 it has the tbi 350 and 4l80e. I have and want to swap in a lq4 6.0 but I don't want to have to switch trannys. my question is how to make my trans shift and functon with an ls engine. I know when guys carb the TBI engines to get the trans to shift the all say you need a holley with a tps. so is that all I need here is to hook up the ls engines tps to my old tps wiring? very confused no-one seems to have done this swap before for some reason there is nothing out there on making a ls work in a truck with the early 4l80e. you would think there would be alot more on it as these TBI trucks just make no power and there are millions of them out there.

 

[df2x4]

I'm not sure what your issue is exactly...

You're going to have to swap to the 0411 computer to run the LS engine. That computer should control your 80E just fine.

 

[joe yuhaus]

well I'm using the fitech easy ls kit. it's just a standalone system for the engine no tranny control. And no all the reading says the ls cpu wouldn't work with my trans. what I need to know is what makes my tranny work now and can I leave all that in there and just wire whatever signals it needs to my new engine.

 

[df2x4]

That sounds like a huge pain in the ass to me. If it were me I'd sell the FITech setup and use a stock 0411 computer with a custom tune to run everything.

Where are you finding that the early 4L80Es are any different than the newer ones as far as wiring and control? The only differences I'm aware of should be cooler line location and neutral safety switch mounting points. (EDIT - And the extra bolt hole in the 2000 and up models for the LS engines, which is a non-issue) Like I said, the 0411 should control your 80E with no issues as long as it's tuned accordingly. Where are you finding anything that says it won't?

https://sites.google.com/site/sloppywiki/everything-ls/4l80e-info

Re-pin your existing wiring harness for a 0411 PCM swap, get the 0411 tuned, and call it a day IMO. Trying to combine the FITech system and the factory TBI PCM sounds like a major headache.

 

[Supercharged111]

There were differences with the 60, and maybe with the 80, but I'm hesitant to think there are with the 80. It was PWM from day 1 and the 6.0 used a flywheel spacer IIRC to mate it with the 80.

 

[joe yuhaus]

no all that is way more difficult and expensive. the fitech system has the harness cpu and tuner all included for 800. it tunes itself or you can custom tune. tracking down a stock cpu and harness will be a few hundred. then getting it custom made and repinned is expensive then custom tuning on top of that no thanks. it shouldn't be that hard guys get these trannys to shift when they carburate a tbi so the stock cpu isn'. running the engine at that point just the trans. I just need to know how to do that exact same thing but with the 6.0 in there instead of a carburated 350

 

[joe yuhaus]

I had this engine with the fitech in my 86 k20 but with a four speed so it didn' matter. as far as the mechanical side of the swap I've got all the handled I know what flywheel spacer combo I need already have the fuel system and motor mounts just need to solve the trans control issue.

 

[df2x4]

You don't need a harness. You just repin the one in the truck. An 0411 PCM with a base tune included from Black Bear Performance is $350. I understand using what you have, but it really seems like you're over-complicating things by doing so. Good luck.

 

[joe yuhaus]

when guys carb these trucks they say the hook the holley TPS to the stock TPS plug to keep the trans working. so I guess all I really need to know other then the stock tps wires what other things need wired to my 6.0 to trick the cpu into running my trans

 

[joe yuhaus]

You don't need a harness. You just repin the one in the truck. An 0411 PCM with a base tune included from Black Bear Performance is $350. I understand using what you have, but it really seems like you're over-complicating things by doing so. Good luck.

but then I have to buy a $500+ custom harness also. I also know zero about computers or repinning things. i know the tbi CPU is dumb it can't have needed that many signals to run the trans. beyond wiring the tps of my 6.0 to the existing wires in my truck I wonder what else I need