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6.5 to vm638

Cumminsfever

Been there, broke that.
Messages
461
Likes
5
Location
Lancaster, PA
Thread starter #1
Yanking out the 6.5 and installing the vm soon. This is just the start of the thread, so I have place to post pics, and interested folks can follow the progress.
So far, we got a flywheel made, and intake remade. Pics will be posted as i have time.
 

tanman_2006

Just a farm kid...
Messages
5,505
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514
Location
Seiling, Oklahoma
#2
I did some reading and saw that this thing is only a 3.8l! That's not many cubes/cylinder considering the power it makes and the fact that it is built like a big rig engine.
 

Cumminsfever

Been there, broke that.
Messages
461
Likes
5
Location
Lancaster, PA
Thread starter #3
Why GM never put this engine in a pickup?? I'll never know. Smooth, and has ridiculous amounts of torque. Takes a healthy cooling system to keep temps in check. Also requires air to air cooler. Aluminum heads don't like high egt!
 
Messages
469
Likes
0
Location
Central Michigan
#7
Can you maybe elaborate on the electronic to manual IP ... ?? Very intriguing to say the least and kinda curious to see how much reliable power can be gotten from one of these.

Mike
 

Cumminsfever

Been there, broke that.
Messages
461
Likes
5
Location
Lancaster, PA
Thread starter #8
Where would someone start when trying scare up one of these engines?
Well, they come in a behring ld15 truck. Those engines have an sae1 bellhousing. Common names to search: detroit ld15, detroit 638, vm638, turbotronic 638, and a mix and match of those terms.

Now, there is a detroit/vm dealer in arcadia florida that can get you any part u need to build or rebuild this engine. I would think they could get you the ups/chevy adapter plate.
 

Cumminsfever

Been there, broke that.
Messages
461
Likes
5
Location
Lancaster, PA
Thread starter #9
Can you maybe elaborate on the electronic to manual IP ... ?? Very intriguing to say the least and kinda curious to see how much reliable power can be gotten from one of these.

Mike
The engine originally came with an electronic bosch ve pump. Same as the early vw 1.9tdi. But we had no ecm to run these engines, so I made a cummins ve pump turn the opposite directon, put a small drive shaft in, and made a long nose on the front. Cummins is a large shaft, short nose, standard rotation. I did this years ago, and ran the daylights out of this engine for a while, but even the heaviest built clutch blew the centers out after a couple thousand miles. Too much torque at too low of rpm.
How did it run? A friend had a 04 dodge that dyno'd 525 on the wheels. He could get away from me, but not real fast. From 0-120 he may have gotten 3 or 4 truck length ahead. This of course, halfton truck to 1ton. I scaled 5200lb, he scaled 7800.

On longevity? I don't know. 33,000 miles of multiple clutch replacements before it got removed. 1 cracked head due to extreme water temps, otherwise, it was a boring engine. It just ran!
 

Cumminsfever

Been there, broke that.
Messages
461
Likes
5
Location
Lancaster, PA
Thread starter #12
Doing some research. Found a VERY similar engine. Mercruiser 4.2l. It even gives a direct injected version of the mercruiser. Hmmm...
Also, the Mercruiser gets taken north of 300hp for marine application. Interesting!
 

Cumminsfever

Been there, broke that.
Messages
461
Likes
5
Location
Lancaster, PA
Thread starter #15
That's a cummins isn't it ??

And isn't the 638 an Italian diesel that Detroit Diesel bought out and just rebadged as their own ???
There is a mercruiser 4.2 "cmd" that appears cummins had a hand in. Actually alot of different versions of the 4.2... One of them has parts interchangeable with my 3.8!

The vm that I have was originally made by vm, then detroit bought it, and put their name on it. As of about 5 or 6 years ago, they quit production of it. Now, back to italy (vm) for parts. Not cool, but at least parts are available!
 

Cumminsfever

Been there, broke that.
Messages
461
Likes
5
Location
Lancaster, PA
Thread starter #18
Underhood sound is very similar to a 6.2, has the typical idi chatter.
the exhaust sound is strangely similar to a 5.9 cummins. Very deep. And when wound out, gets extremely loud. Seems the high compression makes it's presence known in the upper rpm band!

Will definitely get videos of it so u guys can get a feel for what it does!
 
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