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Leak down is 3%
So it has enough compression to run well. It's not sumping. And we will assume that it does not have a rag stuffed up the exhaust.

That leaves tune, and clutch slip.

That dyno sheet looks like it might have some slip in it, but to slip at 95 pounds foot, it would need to be a worn out oem clutch.

That curve could also be from lack of fuel or too much spark advance, or even a bad valve spring.

Do you have a sheet that shows the fuel curve? And what did the sled operator say?

This is typical clutch slip

Rectangle Slope Plot Line Font


Your pull flattens up before it dips, and the the dip is more like a burp. And then its done at 3500-4000.

It really looks like its sumping. When you checked it for that, did you follow the procedure as outlined by the MoCo? Or just walk out and pull the plug?

Past that, all that's left is tune and fuel delivery. Was the tune flashed, or built on the dyno? And what did the fuel line look like?
 

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You have a lot of numbers in that first post. With just a few more, you could put them in one of those calculators to see what your cold cranking compression should come out to be? Those numbers you got from them yesterday sound pretty low for a performance combo. More like a stocker.

I use this one from time to time.

Big Boyz Head Porting - Twin Cam Compression and Displacement Calculator (bigboyzcycles.com)

Not saying this is going to solve your problem, but sooner or later, something is going to shine some light on it.
 

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Make me use my bullet?
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The bottom line here is:

If anybody here will be able to help figure this out, it will be Thermodyne.

Pay attention and give precise, accurate answers to the questions he asks and this will definitely be figured out. Otherwise, you might as well just piss in the wind and hope the answer reveals itself on a cool breeze.
 

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Your dealer needs to give you support. Something is radically wrong. I suspect the tune is at or near the top of the list. Not mentioned is what AF you have. For a test I would make a pull without.
When the tune is jacked the Delphi will pull timing and left unchecked will cull major power.
With the throttle open during the test the numbers would be in the normal range for a performance build with compression releases.
 
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