I know its not 1/2 A but its on the small side nonetheless. I was just given a 1/2 A Pathfinder with a new .074 bolted on the nose. I just started it this evening after doing some preliminary polishing and cleaning of the inside. The engine had a Zinger 7x4 on it. Once running I wanted to bring the rpm's up fairly high . It sounded a bit anemic but tight as well. I gave it a minute or so and then the needle started to work a touch better. The rpm's were coming up but I then shut it off to cool. I was wondering if the 7x4 is a bit to large. I currently use that size prop on my Norvel .15. I was figuring a 6x4 might be better especially at first. I don't know anything about this engine other than its identical to my smaller Big Mig counterparts. I don't think the 6x4 would hurt as I've found these engines to be pretty much bullet proof. I'll take any advice as I don't own the instructions on this one. Thanks, Ken