I tuned an SPE 26 for a guy in Oregon this past weekend. With that particular engine, a few hundred feet above sea level and 70 degrees, it wanted to be about middle of the road for most Walbro carbs. Meaning the low was about 3/4 to a turn out with the high needle a bit richer. It was not a consistent runner and was very sensitive/jumpy about idle trim adjustments. Ran pretty good overall though.