Max Bakerman

I just got a new old 22re pickup and it bogs and has no power when I give it more than half throttle. I just replaced the exhaust manifold gasket as I thought that was the problem but lone behold it still happens. I still think it sounds like an exhaust leak. The sound only happens when I give it more than half throttle, but if I gradually increase the rpms, I can’t hear it. The video posted is a quarter throttle until 3 seconds and after that it’s 3/4 to full throttle when the noise appears. The headers don’t have any noticeable cracks.