MAX-95AX Ring 15.55cc 2-Stroke Engine w/ SilencerO. S. MAX 95AX Ring 2 Stroke 15. 55cc Airplane Engine (including muffler) Designed to replace the 91FX yet retain the same mounting dimensions but with increased power and torque. The design has been optimized to produce strong torque and power at modest RPMs and exploit the extremely effective nature of the E 4040 silencer. This concept becomes important as noise becomes less and less acceptable. The 95AX is another popular sized engine in the AX