83 Chevy 4 door LWB frame swap

[Acsteve247]

Hi my name is Steve I am new here. Recently purchased an 83 4 door lwb truck. It’s a pasture truck that needs full restoration. I have already chosen a local shop to do work but haven’t strarted because I can’t decide what motor to use. My first choice is an LBZ Duramax. I feel like doing the frame swap, putting square body on 06-07 frame, is the best way to go. I want the old school interior. People keep telling me Cummins is the way to go. I plan on making this my company truck and spending 40-60k on this rather than a new one. I DO WANT atleast 1000 hp at wheels and daily driver. I appreciate any advice.

 

[climb-101]

you will soon learn that 1000 hp and daily driver don’t really go together. 1000 hp is hard on parts even if your going easy on the truck. lots of maintenance and work along with a ton of money to make it all happen.

 

[Acsteve247]

Lol yeah I understand I am willing to put he work in to make it possible. I do have friends that run 1000 hp on their LLY Duramax and drive daily one is a tow truck with little issues.

 

[Frankenchevy]

1000hp daily diesel? That’s quite a bit. You mean 1000tq? That’s about what my new truck has, but nowhere near that hp number. I can’t imagine ever needing more power and I tow a backhoe and skid steer around in a dump trailer quite often.

If you do mean 1000hp, that thing will be a beast.

EDIT: now I see your post confirming you DO mean 1000hp.

As to your question of duramax vs Cummins, I’d go 97ish 12v if you we’re swapping into a square body chassis/body. Since you’re going to put it on a newer Chevy frame, I’d just find a duramax truck/chassis to swap your square body onto.

Best of luck! Throw up some pictures of the project. I’m sure many are interested in this project based on the 1000hp figure.

 

[Acsteve247]

Will definently post pics as the project goes on. Bought an 89 suburban for the front clip and interior. I Understand 1000hp is a lot but when I am done there will be no other square body like mine on the road, well atleast I haven’t found one.

Do you know of any sites that sell kits for the frame swap? I have tried googling it numerous ways and can’t find anything but hear of such sites.

 

[Frankenchevy]

Someone did this exact swap a few months back on this site. Try searching, it can’t be that far back.

 

[Acsteve247]

Awesome bro I will search for that! Thanks for the input.

 

[roundhouse]

At least it will be tax deductible for the company

 

[climb-101]

look up RTech Fabrications in Hayden, Idaho. they do some awesome work swapping bodies. there the earlier body style but it will give you some ideas.

where you located at? i know a few places that have done body swaps and i have done a few as well. we’re all up in montana though

 

[Acsteve247]

Roundhouse my CPA told me to spend some money or give it Uncle Sam. I like the square body more than the IRS!

 

[Acsteve247]

Climb 101 thanks bro I am in Houston Texas. The shop I brought it to can do the frame swap or put a motor on my frame. I am just doing research on my own to see what it all entails and which one I would rather have. I like the idea of newer suspension and brakes especially with the power I am looking to make.

 

[roundhouse]

Yeah

My brother has a small biz on the side for tax deductions
He buys a new crew cab 4wd every 4 or 5 years
It’s either that or pay it in taxes

The squarebody frames were flexible when they were new

40 years later with 5x the power it’s going to be spaghetti

Your frame would need extensive boxing and reinforcement

You just need to get 90s model Pete or KW and narrow the frame and drop your body on it

You’re not expecting an automatic transmission to stand up behind a big power diesel are you ?

 

[Acsteve247]

Wow I never thought of that option I would love to research dropping it on a semi frame. As far as automatic transmission I am gonna have to have a special built one if I want automatic but I prefer standard clutches are easy to replace.

In my original post I talked about 1000hp and that’s what my buddy’s tow truck has. I spoke with him this morning though and he has a programmer he can adjust on the fly and normally runs a 600hp tune that has around 1100 ft lbs of torque. Nothing has been on a dyno the setup he has says it puts out those numbers so who knows. He has an upgraded turbo, exauhst and intake. He has only ran the 1000hp tune a few times, one of which is when I rode in it. His stock transmission has a shift kit but nothing else. He said I would be it’s trying to drive 1000hp everyday, it’s just there if you need it.

 

[roundhouse]

I don’t think you’d notice more than 400Anything more than that will end up as wheelspin or broken parts

Most 18 wheelers have 350-450 HP and 1100-1600 torque from a 900 cubic inch engine

If I were building your truck I’d use a pre computer engine
Probably a Cummins with a spicer 10 speed manual

There’s some build threads on CK5 and pirate 4x4 for swapping in themedium duty or heavy duty manual transmissions

On the engines with computers the parts cost 3x and on the engines with computers and emission junk, EGR, DEF etc. the injectors and pumps are unbelievably expensive
Not only to buy but to have someone redo the wiring harness and tune it etc

I think the CUCV models and some 3500s K30 had a stronger frame