Nico71 - Lego Switchless Pneumatic engine mk2. With stacked 4 valves instead of side by side, one cylinder and two speeds gearbox. Expected to me mounted soon in a two wheels creation
Lego Technic MK3 V8 Pneumatic Engine - 10x More Power! 1500 RPM! LPE MOC + 6 SPEED Gearbox Test - YouTube