With no baffling, yes. Also, had problems getting jetting correct and cylinders running very uneven. Originally, I just directed the flow over the cylinders and then they ran even and was able to reliably jet it. On long uplines, it does get warm however. Gettng in-air temps climbing up to 320-330 (depending upon ambient) on really long uplines (just flying around about 260F). Measured at the back of the cylinder near the top. Been wanting to try defelcting air around the cylinder to see what happens. Engine seems to be ok at those temps, but would like to keep them a little lower, especially in higher ambient temps.