It's out of a weed whacker and it said it was a 30cc. I have a couple of 25s and they look a little different. The carb throat is pretty small, though. It flys a 17lb. Tigermoth in a scalelike manner, but I would like a little more power in aerobatics. The muffler is a modified stock one with all restrictions removed. Maybe a larger carb would be enough for me. Where do you get them?