M1008 CUCV Hot Rod Project L92 engine 6L80e transmission Swap

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evldoer

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The second pic is the original passenger side manifold. There was no way we could make this work without cutting away too much of the top of the frame. That is why the f body manifold was put on. The other pics show the front crossmember clearance, and some other shots to show how things are going together.
 

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evldoer

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We added about an inch and a half in height to the crossmember to gain the proper clearance for the front driveshaft, and get closer to the factory pinion angle. Crossmember in this truck was bent, but we worked with what we had.

Transfer case is on, and both driveshafts are on. They both fit almost perfectly and will not need to be altered. Front driveshaft is bent and will need to be replaced, but for now I'm just installing parts to see what will need modifications.
 

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Another Ahab

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We added about an inch and a half in height to the crossmember to gain the proper clearance for the front driveshaft, and get closer to the factory pinion angle. Crossmember in this truck was bent, but we worked with what we had..
I remember reading somewhere about how that's the typical reason for early failures on trucks from homemade lift kits:

- the change in connecting angles everywhere can cause strain and increased wear on components.
 

evldoer

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A few new updates on this project.
We used the original cucv radiator and fan shroud. The fan does not extend into the shroud far enough so we will find some similar black plastic to attach to the shroud to extend it so nobody loses any fingers.

I made 2 adapters out of aluminum to step the gas motor hoses up to the size of the radiator inlet/outlet size. On the upper adapter I drilled and tapped the adapter to plumb in the steam vent hose from the cylinder heads. The 3/8 hard line was bent to follow the radiator hose to hide it a little and help support the hose a little.

We mounted the fuel pump and fuel filter/regulator on the frame rail. Used a walbro 255 and a corvette fuel filter. This filter has an internal fuel regulator so it diverts excess fuel back to the tank. I plan on making a shield out of aluminum to protect the pump and filter from heat from the exhaust.

We put in a new fuel tank and fuel sender stalk so we didn't have to clean out the old tank. No modifications were needed on the sending unit stalk. After the fuel regulator we connected the fuel line to the original hard line that feeds the fuel injector rails
 

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evldoer

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The engine ECM was mounted on the drivers side inner fender, and fuse panel for engine controls was mounted on the firewall. The relay next to the fuse panel runs the fuel pump. I will tidy up all the wires when I'm done. I need to extend the wires for the diagnostic connection so I can mount it under the dash inside the cab, and will wire in the service engine light into the istrument cluster. I will probably use the water in fuel indicator since that won't be needed any more.

We used an original 2008 chevy truck air filter box, and it fits well where the front battery used to reside. By using the factory air box we are eliminating the need to have alterations done to the factory fuel injection tune. These engines are very sensitive to any physical changes in the intake plumping.
 

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evldoer

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This engine uses an electronic Throttle pedal, so we had to make a bracket to mount it to the firewall. We utilized the original mounting holes so there was no drilling required. Just fabricated a plate that is bolted to the firewall from the inside, and the pedal is mounted to the plate.
 

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evldoer

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The truck is running and can move under its own power. Right now the exhaust has 12 inches of pipe off the motor so I could get the oxygen sensors mounted. It is scheduled to go in to an exhaust shop may 5th to have the rest finished. We need to get the seat mounted back in the cab and the driver door on the truck. It also needs new tires put on. Looking forward to taking it out for a test drive!
 

evldoer

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that is gonna be one sweet ride...how much did the complete engine setup as delivered to you cost if you don't mind?
I'll let Truckhead reply to your question, but keep in mind that this engine and trans combo has the highest performance of the ls truck engines, so there is more demand for this version. There are other combos that can be picked up for a reasonable price. 400 horsepower and it is smooth.
As soon as I have time to give the truck a good inspection it will be time for a test drive. Results will soon follow

We hooked up the towbar on Friday and towed the truck in to Fond Du Lac to have the exhaust completed at a custom exhaust shop. It now has full exhaust with a pair of stainless Magnaflow mufflers. Sounds really nice.
 

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albersondh

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My LQ9 from 08 2500HD 4x4 came with a 6L90..... Having to change out the transfer input to take the huge 6L90 shaft. Found a gear that will make it happen but what a PIA compared to 6L80. If only I had known then what I know now....

Nice work! NEED MORE UPDATES.
 

trukhead

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hOWDY fOLKS!

It's been a while, life happens! The CUCV L92-6L80E is an unprecedented success! Pictures and operation videos to follow very soon! The exhaust was bent up for the truck and sounds nice. It's dual all the way back to megaflow performance mufflers. The truck has a nice bark to it yet an Idlely quiet at cruise.

The 6L80E is the only way to Fly! The 6th gear is .6 over drive and it whips them 4.56 gears right into shape! The drive shaft was fabricated a bit heavier and 3/4 of an inch longer and super balanced. I was chasing evldoer and it took me to get up to 90 to catch him! I took CUCV out for a spin and Oh My! I got a hot rod!! This is Cool! The L92 engine just purrrrsss! The 6 speed is a bit unusual but nice, it does a lot of shifting up to 4rth gear. Funny, Fun thing is ; you got 2 more gears and the fun begins!

The Engine ECM is just stock tuned with the features turned off to allow it to run the engine and tranny stand alone. evldoer suspects the tune is only making 300 ish horse power right now. Well I'll tell you, hang on when you apply the go-pedal cause it goes!

The issues I have is the power vs suspension. there is far too much power for the suspension as it stands. Thing is that is just how I like it! LOL! What I am saying is once the conversion is completely finished, the next project will be tuning the suspension.

Turning onto 49 off a YY, I stood on the go pedal, the weight distribution and shift caused this machine to wallow and steering correction only exacerbated the wander. Like trying to catch a trout in a stream with your bare hands, all wiggly and squirmy and FASSSTTTT! After about 60 I had to ease up and CUCV the wonder truck fell right in to line and went down the road straight as an arrow! Proceed to step on go pedal again and truck just went down smooth road as nice as you please! And the Brakes are Great!!! The brakes bring speedy right down! On a bumpy road at cruise speed the bump and oscillation need to be addressed as well.

Some Ideas for the suspension are much lighter rear springs, gas shocks. Right now, It appears the rear springs are even heavier than what is on other CUCV's I have had and seen. So the rear end is up and the front is also up a bit as well as the L92 and 6L80E is lighter than the diesel that came out. With the rear end up, I think the caster and chamber are tilted to the front and that contributes to the wallowing wander under hard acceleration. When driven like a normal sane person should drive, Speedy the CUCV is fine BUT...... The load carrying capacity and the speed this machine is capable of do not match so serious suspension tuning is in order for me. This truck is easily capable of cruising 80MPH on the expressway, (If you have the driveshaft for it). I am thinking if I want to carry heavy loads, I will use a stock CUCV and keep it slow. This CUCV is a high performance machine now and needs to be tuned.

I was informed by evldoer that the transmission shifts the way it does because of the torque modulating programming in the transmission controller, I like it and will likely not turn it off when optimizing the tune.

I have yet to unlock the full horse power from the engine and the suspension and tires also need to be up to the task. The axles and steering linkage need to be serviced and inspected as well as the brakes. The good thing is the CUCV started with about 22,000ish miles so the truck is pretty tight yet. A cruise control and a gear selector push button gizmo and possibly air conditioning. But one step at a time, get the CUCV engine conversion finished.

:mrgreen: :hammer::driver:
 
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trukhead

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that is gonna be one sweet ride...how much did the complete engine setup as delivered to you cost if you don't mind?
The engine package was about $6,300 ish with basic ECM Flash and harness trim. There is about $2,300 in parts and exhaust as well. But it was easy to go with the new fuel tank and exhaust and other parts!
 

trukhead

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I am bringing this thread out of retirement!

CUCV the hot rod truck is operable and tame as a fed contented jaguar!

Ggeesh does it have speed!

It is very driveable and mannerly.

pictures to come very soon and a youtube video.

Would I do it if I knew then what I know now? oh Heck Yes!

One thing I would do different is consider a direct injection 2015-17 5.3 and the 6L80E 4x4 tranny. I bolts right up to the 203 transfer case.

cheers

:beer:
 

86m1028

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Mind breaking down the exhaust cost ?

Ive got a 2010 gmc 3/4 ton 4x4 (6.0/6 speed auto) that Im planning on using.

Got any pointers that you haven’t mentioned in this thread ?
Thanks for the pics & info.
 
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