OilHead, yes I have tested about all the saws I can get my hands on. From what I have found, if the carb makers are paying any attention at all to the pop-off pressure on their carbs for stock saws, they must be on a secret mission to conceal their knowledge...ie, the pop-off pressures are all over the board. A 242xp that I tested today, had a pop-off pressure of 34psi! More often than not, I'm finding stock pressures above 20psi. Don't know if you saw the email I posted from Walbro on the subject.... Basicly, a
guy there said it doesn't matter on stock equipment, but did go on to say that in racing engines, like in karting, the pop-off is more critical. I guess that they think it is out of their jurisdiction to have to respond informatively to any question that goes beyond stock engine requirements. Unfortunately, they act totally vague on the subject. I still haven't exactly settled on what I find is best for my modded saws, but I doubt it is 34psi.