CK5
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'86 Jimmy 4in Lift, 40’s, tons, 8.1 Swap- 700r4 said PNNNNN

This is not a dedicated trail rig, but does trailer to the destination usually. I am currently in the planning phase of doing a 52/56" spring swap, and getting back to being more road worthy.
Finally got the 8.1 out of the back of the diesel tonight after borrowing my brothers engine hoist.

Put it on the engine stand and started looking it over.

Block is fine and the internals look amazing. Top end revealed a missing push rod. Shop said it had upper end noise. Looks like this might be an easy rebuild.

For now it goes into the corner for future vroom vroom noises.

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Finally got the 8.1 out of the back of the diesel tonight after borrowing my brothers engine hoist.

Put it on the engine stand and started looking it over.

Block is fine and the internals look amazing. Top end revealed a missing push rod. Shop said it had upper end noise. Looks like this might be an easy rebuild.

For now it goes into the corner for future vroom vroom noises.

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Another distraction? :dunno:

I want to know how a pushrod randomly goes missing without leaving any pieces behind. :dunno: :thinking:
 
Another distraction? :dunno:

I want to know how a pushrod randomly goes missing without leaving any pieces behind. :dunno: :thinking:
Not much of a distraction. More of a “planning for the future” moment. Eventually this K5 will have an 8.1, TH400, 203/205 doubler in it. My dream drivetrain. I now have all parts of the main drivetrain. Just need to rebuild them all and make them fit.
Remember when you were a kid and you used to sneak out the window at night? Well that’s not how it happened.
I’m guessing when they pulled this engine they found what was the issue, but said “eh oh well, we got our money”.
 
Diesel, diesel, diesel. That's a diesel TH400. Remember that before you throw it behind a gasser.

Though a BigBig block might not mind the low shift points. ;)
It’s gettimg a full rebuild before it goes in. Along with a reverse manual valve body.
 
Block is fine and the internals look amazing. Top end revealed a missing push rod. Shop said it had upper end noise. Looks like this might be an easy rebuild.
That will be a great power plant. Nice score.
If it’s truly a dream drivetrain skip the 203 and go with a planetary box.
+1 The magnum box shifts very smoothly, plus you get more low range combinations.

David
 
Sooooo why dont we have a 3:1 203 gear set. Seems like it would be less than a lowmax because its essentially one gear. Hmmmmm
 
Hey @Kay86K5 did you do anything extra to your engine like a cam or anything? Or did you just leave it stock with good exhaust and a good tune?
 
Hey @Kay86K5 did you do anything extra to your engine like a cam or anything? Or did you just leave it stock with good exhaust and a good tune?

Internals of my 8.1 are completely stock. I have a nice spectra air intake, good flowing exhaust with headers, and a custom tune by Team 208 Motorsports....and it lights up my 285 bfg's on my 7k lb truck on command. Very happy with the power
 
Eventually one day I'll probably throw a cam, heads, and ported intake on this thing and really get it to sing (well, at least a cam, haha). But as you probably know, building 8.1's are freaking expensive, hence why right now I just left it stock with a tune so I can enjoy the truck for a while and build funds to throw some go fast goodies at it later
 
Internals of my 8.1 are completely stock. I have a nice spectra air intake, good flowing exhaust with headers, and a custom tune by Team 208 Motorsports....and it lights up my 285 bfg's on my 7k lb truck on command. Very happy with the power
I'm really only interested in the low end torque for crawling. Do you feel everything feels good enough for a properly geared crawler on 40's? I remember how my old 8.1 ran, but it's been a while.
 
I'm really only interested in the low end torque for crawling. Do you feel everything feels good enough for a properly geared crawler on 40's? I remember how my old 8.1 ran, but it's been a while.

For sure...would work great!

Are you planning on running the DBW setup, or converting to cable operated throttle body? I have the DBW setup on mine...and I will say this is probably exaggerated by the fact that I have a manual NV4500 behind it, but the throttle is a little touchy. Luckily mine is a tow rig so I never really have a problem with it, but I could see it being somewhat annoying for crawling....But again, I will say, I think it's because I have a manual behind it. I think an auto you probably wouldn't even notice it at all. But I now see why Larry converted his to cable cause both of his are manuals and he "wheels" both of his too. If street driven mainly or have an auto behind it, I believe the DBW will be fine
 
For sure...would work great!

Are you planning on running the DBW setup, or converting to cable operated throttle body? I have the DBW setup on mine...and I will say this is probably exaggerated by the fact that I have a manual NV4500 behind it, but the throttle is a little touchy. Luckily mine is a tow rig so I never really have a problem with it, but I could see it being somewhat annoying for crawling....But again, I will say, I think it's because I have a manual behind it. I think an auto you probably wouldn't even notice it at all. But I now see why Larry converted his to cable cause both of his are manuals and he "wheels" both of his too. If street driven mainly or have an auto behind it, I believe the DBW will be fine
I liked my DBW setup on my 2001 2500 rig. It never felt too jumpy or bouncy, so I'll probably go that route for ease. But we'll see how it actually feels in a crawler. It may be a totally different feel.
 
Depends on the tune also. His tune may have taken the “delay” out of the dbw. On my hemi I took the dbw lay out and it was like finding a whole shit ton of torque.
 

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