RM Sotheby’s Driven by Disruption Auction takes place on December 10th in New York. While the auction itself is peppered with a number of wonderful Porsches for sale, including Janis Joplin's "History of the Universe" Porsche 356, we've found what may be two of the most unique lots we've seen in some time. Hand crafted, runnable, 1/3 and 1/4 scale miniature Porsche engines. And not just any engines, one is a scale version of a 904 and the other is a scale version of a 917.

Lot 126 Porsche Type 904 Carrera Miniature Engine

Herb Jordan was a man of vision. A Porsche enthusiast at heart, this Canadian engineer and inventory became known as a brilliant model maker. Having studied Porsche's factory manual, Herb decided could build a four-cam Type 904 in miniature. One-third scale to be exact.

Over the course of two years Herb invested over 2000 hours in the project. Ever piece of the miniature Porsche engine was manufactured using a 10-inch lathe, milling machine, shaper, and drill press in his home workshop. No castings were used; the case, crankshaft, heads, and two-ring pistons were all machined. The carefully finned alloy cylinders used shrunk-in iron liners.

This miniature Porsche engine displaces just 45 cubic centimeters on slightly over-square dimensions of 25.4 millimeters by 22.2 millimeters. That's just a touch out of proportion to the original 2.0-liter used in later 904s. The twin downdraft carburetors are miniature copies of Weber IDAs, each made of 50 individual brass parts. Herb loved to demonstrate his little motor to appreciative groups and would run his creation on methanol fuel. Though said to be fully functional, the model has not been run in nearly 30 years and will require careful service prior to any further operation. This unique miniature Porsche engine weighs approximately 10 lbs and measures 12 inches wide by 12 inches long by 9 inches tall.

For more information, or to learn about bidding, see the original listing on RM Sotheby's site.

Lot 127 Porsche Type 917 Miniature Engine

If you thought Herb Jordan's Type 904 miniature Porsche engine was impressive, get a load of his 917 miniature version. His flat-12 displaces just 54 cubic centimeters and can spin at a mind boggling 24,000 RPMs. The crankshaft is machined from a single billet. The gear-driven mechanical fuel injection pump is the size of half a pencil. Tiny oil lines are even properly wire-braided, and the engine features beautifully machined and finned cylinders and cam covers. With 8.5:1 compression, this miniature Porsche motor can produce “more than sufficient” horsepower on methanol with the help of two tiny turbochargers. Like the miniature 904 engine above, this flat-12 engine has not been run for years and will require careful service prior to any further use. The engine weighs approximately 15lbs and measures 15 inches long by 8 inches wide by 7 inches tall.

For more information, or to learn about bidding, see the original listing on RM Sotheby's site.

Each lot has a pre-auction estimate of $20,000 to $30,000. However, it should be noted that both are selling without reserve. So, depending on who's bidding these little beauties could go much higher or someone could get the steal of the century for their collection.