Constructing tiny replica or modified versions of full-scale engines is a little-known hobby with a rabid fan-base. It boasts adherents to the art of building tiny steam engines, radial engines, all manner of V-engines, single cylinder motors, vintage agricultural engines, and experimentals, along with what we see here, compressed air powered miniatures. Compressed air engines are sort of the marijuana of miniature engines, just hardcore enough to keep the sissies out, but sort of a gateway project, leading to crazier and crazier builds with honest to goodness miniature internal combustion with all the implied complexity.
This example is one of the smallest examples of a V8 we've ever seen and it was built to emulate the Chevy 350 in look if not in function. The video shows the motor in an early, undecorated iteration running on 65 PSI of compressed air for a sustained 38 seconds. It may bot be internal combustion, but take a look at the impossibly small components and you can appreciate the build anyway. Check out the hand built and pressed together crankshaft, the tiny connecting rods and pistons, it's all very impressive.
Until you look at Steve's next project — a cast V4 engine called PeeWee with real-deal internal combustion and a functioning coolant circulation system. See what we told you about compressed air motors being a gateway project? [Florida Association of Model Engineers , Youtube]