Open the muffler up or add another outlet to about 80% the size of the exhaust port, fine tune the carb afterward and keep the air filter clean as possible. I usually start with a clean air filter, then pop the cover off the air filter when refueling and tap off the excess to keep it from clogging. Use premium fuel with good oil and it should keep running very good and strong. I have run several both the 034 + super-36 versions and everyone has been fairly fast, running strong chainsaws, and very reliable. Never have run the larger displacement alongside the original 034 but have run a couple o34's later down the road after running o34 supers and haven't noticed the differance. Both run a 20" 3/8's bar with plenty of umph and speed to me.
I am not a saw builder so I can't tell you specifically more then that. I bought an 026, first attempt woods ported as far as I know, and it winds out pretty good with I believe a bit more power then stock but it still doesen't feel close to an 034 to me. It also is reluctant to start cold, don't know if porting had anything to do with it for sure, but I think so. It usually takes 10 to 20+ pulls to start it cold so I don't use it much. For some reason it feels to vibrate less then other 026's I run though.
When replacing the piston in my 044 last summer I filed with hand files and emory cloth the intake and exhaust ports. I didnt take much off and I polished the exhaust port very smooth . Originally with 135lbs of compression this 044 didn't feel much stonger then any 034 I had run, but afterward it rips. My friend has a fairly new broke in stock 372 and when he run the 044 he said he thought it was close to it and it feels to me it is also (maybe someday soon we'll see,but since Ive been bringing my o44 out, he has been leaving his 372 at home). Before it didn't feel close. I am not sure if my gains were more from the new espian piston and rings or if my filing and polishing played more into it.