Lego engines powered by compressed air are always a sight to behold, but sometimes they can be cumbersome contraptions that are too complicated for their own good. This tiny plastic eight-cylinder isn't like that, however. The engine's builder claims it's the world's smallest Lego V8, and despite it having a few 3D-printed parts, I believe him. Heck, it even sounds like the real thing.
The little engine in the video revs as high as 4,350 rpm. Its incredible Lego parts are able to stay intact at those speeds, especially considering the seeming lack of lubrication. Not everything here is OEM Lego, though. The creator mentions the crankcase is a 3D-printed part not of his own design, and the crankshaft and valves are custom, too. Interestingly, the valves that control the airflow are from tire valve cores.
This unit is likely a two-stroke. ICE-adjacent compressed air motors like these often do not have a distinct compression or intake stroke, just a combined power/intake and exhaust stroke. That doesn't mean it's functionally any different than a big V8, of course. And since it has a cross-plane crank, it even sounds like the real thing.
Similar Lego engines we've seen before use the brand's sealed pneumatic cylinders as opposed to the actual mock engine/piston sections seen here, which are also factory Lego parts. Those motors are capable of more efficient sustained operation and are even powerful enough for use in a self-contained air-powered vehicle. So far, the engine in the video we're seeing today is only driving a flywheel. It looks and sounds a lot more like an actual engine, though, which makes it just as cool in my book.
Why Lego doesn't make a working engine kit based on something like this is one of life's great mysteries.
Got a tip? Email us at firstname.lastname@example.org