Check the listing for details. Zenoah Marine Engine 30cc Redline Pro Mod. Condition: New. Listed at 595.00 USD. Zenoah PUM Modified Engine 30.5cc This Zenoah PUM Modified Engine has all of the torque and RPM you need and a whole lot more, 2mm stroker crank for more bottom end! This engine is set up for heat racing. Mods include increased compression, raised exhaust timing and reshaped and enlarged exhaust port. The transfers opened up and reshaped. The intake opened up and timing changed. The piston has been lightenedand the excess material from the inside has been removed via CNC machine, top of the piston has been relieved to prevent piston seizures and skirts trimmed on sides to enhanse the transfer flow. The Walbro WT-257 Modified carbuerator bored out and entry angle reshaped for better flow. Now with Zero Drag Seals and Aluminum ZRC carb iso block and a NGK CMR7H spark plug installed. Motors run around 8 hp, max HP runs at 16,500 rpm range. These motors will run up to 19,500rpm. This motor does not come with a motor mount or a collet.