Miniature engines may not be practical from an auto enthusiasts standpoint, but they’re definitely nice conversation starters nonetheless. We’ve rounded up five of the most incredible examples for your viewing enjoyment. Continue reading to see them all.

5. Quarter 4-Cylinder Engine

Built by George Luhrs, the “Quarter 4-Cylinder Engine” is touted as the smallest of its kind. It took him approximately 600-hours to complete and no details were spared during the build, as you can see from the images above. Hopefully, we’ll get to see this installed in a mini vehicle sooner than later.

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4. Paper V8 Engine

This fully-functional V8 Engine was made entirely from paper by Yeesjob, with the exception of its internals. It sports many moving parts, including a compound crankshaft, a rapid cooling fan, and a complex compound gearbox etc. The engine is powered by 2 x 1.5V D batteries and weighs 6.6-pounds.

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3. Air-Cooled 4-Stroke Mini V12 Engine

Despite it being designed for R/C models, this 4-stroke V12 engine is touted as the world’s smallest. Featuring a 21mm bore, 87cc displacement, air cooling, and two camshafts.

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2. LEGO V8 Engine

Yes, an auto enthusiast has built a working V8 engine using just LEGO parts. This tiny engine peaks at a maximum of 1780 revolutions per minute, which was made possible by adding timing gears in the rear to prevent torsion in the crank and cam. Currently, it’s running in a double cam setup.

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1. World’s Smallest V12 Engine

Sure, you can’t stick this tiny V12 engine in a car, but it’s fully capable of running when powered up. In addition to the inspiring movie music in the video preview, you’ll see that it’s “constructed with a combination of stainless steel, bronze and aluminum; the finished product runs off of compressed air and has a displacement of 12 cubic centimeters.”

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