All you "factory" needle setting fanatics need to go to the Walbro web site and read the tip of the month about needle settings....They now leave Walbro calibrated for the ORIGINAL equipmnent user (IE chainsaw or weedeater) set from 1/4 to 4 turns open..Anyone thinks that will work on a model airplane gasser lives in never never land..Check it out, maybe you just might learn something from the engineers who actually know [>:]