Go-verticle, The 2.3 if it refers to cubic inch would equal about 38 cc. 38 cc is actually 2.32 cubic inches. If the engine is that big and from looking at the pictures it could be, you will have plenty of power. I would leave the port timing alone. You need to put a good muffler on it so it breathes. As for the carb on it, again assuming it is about 38cc you need a carb venturi in the 13 mm range and a 34/64 on the intake side. That is an older engine and my experience with them is that the ports are timed very well. Consider that it runs in a saw designed to scream all day long. Consider that a weed trimmer is choked back to prevent over winding the engine if the string (read prop) gets too short and joe homeowner keeps going and over revs the motor. I do many Echo trimmer and saw engines. The saw motors are stronger. I do the same ones BME uses and I am sure he doesn't take the engine apart to cut the ports. However I have played around with port timing and have made some nice improvements in performance. I have also gone too far and killed a few. But I would not even consider doing it if I didn't have the Bridgeport in my garage. Good luck and get some experience with this one and then take another step. By the way Ken Lambert and Scott at Brillelli make fine mufflers. I use them both.

Tim