Does this sound right

Here’s an example of almost the exact same scenario.
The tq curve is heading downward, then at 6600 there’s a little upward blip, then it continues down after that.
It did not do that on most runs.
If you look at the tq at 6500(388) and 6700(381), and averaged those two(384.5), the real hp number at 6600 would be more like 483.

It’s important to understand what you’re looking at on the sheet.
The dyno isn’t “measuring” horsepower.
It’s measuring torque, and calculating horsepower.
Little blips in the torque curve that won’t repeat from run to run……. Are just that. Blips.

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I have one of my Dyno sheets that did the same thing.