Model Engine Builder

An engine you build by hand, then start. Six model engines, from a single-cylinder diesel to an inline four. Each one goes together part by part on the bench, gets torqued to spec, timed and oiled - and then you spark it and find out what your hands were worth. FOUR STAGES BETWEEN A BOX OF PARTS AND A RUNNING ENGINE 1 - ASSEMBLE Drag every part onto the blueprint in the order it goes together. Crank, piston, rod, head, cam. The tray tells you what is next. 2 - TORQUE Work each fastener to its spec. Too loose and the engine rattles itself apart. Too tight and you strip the thread and pay for it later. 3 - TIME AND OIL Set the valve timing against the marks, then pour oil to the fill line. Stop short and it runs dry. Overfill and it smokes. 4 - FIRST FIRE Spark it. The engine either catches and settles into a note, or it misfires and you hear that too. Every engine sounds different - the diesel thuds, the two-stroke rips, the four smooths out. IT ALL ADDS UP Assembly, torque, timing and oil each score out of 250, so a perfect build is 1000. The engine's final RPM comes straight from that total, and the spec sheet at the end shows exactly where you gained and lost. BUILT FOR ONE THUMB Drag, hold, tap. Haptics throughout - you feel the part seat, the wrench click, the engine turn over in your hand. Every engine has its own idle rhythm. No accounts. Plays offline. Three engines free; watch a short video to open the rest, or remove ads once and unlock everything.