I have noodled beech and oak boards with the 36" bar fully buried, my PS-7900 has no issues pulling that setup whatsoever.
My stock Dolmar PS-7310 with just a mild muffler mod will also pull my 36" B&C setup.
She even feels faster in the cut as long as the bar tip sticks out of the other side of the log, but once buried one notices that she lacks a little bit low end grunt over her bigger sibling the 79er.
Check out my YT channel, nothing staged, all imperfect real life performance.
Look into getting a 73xx or 79xx, of the two the 7310 is the secret undeclared factory hot rod once You remove the mufflers SLR.

Four more months till the annual NY GTG, save up till then and buy a brand new saw, sure beats fixing a raped and abused unit.
I dare say that the 7900 is THE saw Stihl and Husqvarna wish they came up with two decades ago (my PS-6400 is made 2001., my PS-7900 is made 2003.).
A little eye candy . . .
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