12 Valve swap

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brandontwilson

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1976
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chevy k20
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6.7 cummins
So i'm converting from a gas to a 12 Valve just curious on what all i need to change and get if someone wouldn't mind letting me know it would be much appreciated
 

1lejohn

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There is a bunch of info on U-Tube of these builds. The first step is welding the front frame for added strength. Do to the weight of the engine and the torque it will produce. I think someone on here has a build thread going . You can do a search to try and find the thread.
 

squaredeal91

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5.9 Cummins 12 valve
This is a loaded question. Depends on what you want and have a budget for. Biggest question is what transmission your Goin to use. They make adapter plates for almost anything. I've got a 12 in mine with a zf5 behind it.
 

brandontwilson

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6.7 cummins
This is a loaded question. Depends on what you want and have a budget for. Biggest question is what transmission your Goin to use. They make adapter plates for almost anything. I've got a 12 in mine with a zf5 behind it.
i was just gonna get a adapter plate so i can use my th400 or if i can find the actual transmission i was gonna use that
 

vr1967

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Depends on if its going in a 2wd or 4wd. And it’s intended usage. Running stock? Or intending to increase power?
I’ve done a few Cummins conversions, but everyone seems to have their own idea of what is the best way to do it
 

squaredeal91

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Greg bush
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1991 SB
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K30
Engine Size
5.9 Cummins 12 valve
i was just gonna get a adapter plate so i can use my th400 or if i can find the actual transmission i was gonna use that
You mean a Chrysler transmission? Im not a big fan of there newer automatics. I would stick with a gm transmission if your going auto.
 

brandontwilson

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chevy k20
Engine Size
6.7 cummins
Depends on if its going in a 2wd or 4wd. And it’s intended usage. Running stock? Or intending to increase power?
I’ve done a few Cummins conversions, but everyone seems to have their own idea of what is the best way to do it
its going in a 4wd pickup and for the time being itll be stock up until i can beef everything up for it so long run there will be a increase in power if that makes sense
 

squaredeal91

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5.9 Cummins 12 valve
If I'm pretty sure the GM adapter works with all there truck transmissions witch is cool in case you go with an overdrive transmissions down the road. I'm curious as to what starter they say you will need.
 

brandontwilson

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brandon
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1976
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chevy k20
Engine Size
6.7 cummins
If I'm pretty sure the GM adapter works with all there truck transmissions witch is cool in case you go with an overdrive transmissions down the road. I'm curious as to what starter they say you will need.
yeah that one im obviously not gonna get everything overnight it'll take a bit of time but i'll watch some youtube videos and see what they use and what'll work with my budget lol
 

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