Need help- my car is BOGGING, here is my dyno

Need help guys..When accelerating my car boggs/ hesitates above 5000 RPM.
The feeling it's kinda 2nd cam kicks in at 3300 RPM (I know that's normal).
But the problem is my car is hesitating after 5k all the way to redline. Sometimes it's hard to tell. But the dyno shows it all. It's been over a year now and the problem didn't go away
My mods are: steeda pullies, borla catback, magna X pipe with cats. See, my car is almost stock, no chip and timing is intact.
Here's what I have tried recently: new platinum plugs, Ford 9mm wires, fuel filter, put stock MAF meter back on (had C&L), even added injectors cleaning treatment...Yesterday put the car on dyno... all the same, just like the last year, just A/F ratio went richer to 12:1
I have no check engine light. Just to make sure, I even went to Autozone, and as expected- NO codes whatsovever.
I know something is wrong. Any experienced help would be appreciated. Thanks guys,
97 cobra, 65xxx miles.

DBMSTNG said:

yuor car is knocking then pulling timing alot! that's why your hp and tq jump around so much. do not race the car until it is properly tuned. try a colder spark plug.

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I was thinking it was knock sensor... But There is no knocking sound. And the guys at the dyno shop could not hear detonation either.
Could be that the sensor itself faulty?

DBMSTNG said:

you can have detonation and not hear or feel it. it may be the sensor, check it out. try running a little race gas to raise the octane level. if the dyno still shows all those jumps, it's most likely the sensors because with race gas, it would be very unlikely to knock.

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Thanks, I'll ckeck it out.
But I don't think this is detonation : I live in colorado, 5000ft of altitude (25% less atmospheric pressure than at sea level) and fuel octane requirement can be reduced by 1 octane for every 1000ft.
So technically I could put 86 octane fuel and still be ok..
Again, to clear all doubts, I never did that to my car. I always put premium/91 brand. So race fuel doesn't apply to me. But I'll try it anyway.