OK i have the new muffler on and modded to look like yours in the pic. and have carved out the deflector plate. and there is no spark arrestor. I am ordering a tac at some point next amazon purchase. So right now i have no tac. But saw starts and idles fine and chain does not spin even with a looser than ideal chain. I hold the saw WOT and then turn till i hear bogging or 4storking. Then turn till clear then back till just bogging. When i release the throttle and then pull it WOT again i am bogging worse than i was when i had just messed with it. sometimes it will clear up after a second or 2 but not instantly. If i set it right as it bogs while holding WOT is is a dog in wood? Any ideas is it a TAC issue with RPMs as my L and LA screw may be out of whack, or is it a possiblility i need to clean the carb again or there it is sucking air somewhere? The saw had issues about 2 years ago. I thought it was a carb so i rebuilt it, and reinstalled. I then had the same issue and saw that i was sucking air through a split in the main fuel line from the tank to the carb. replaced that and no problem fixed. Just point me in the right direction and i think i can handle it.