The Porsche 917 engine, with a pen shown for scale. Images courtesy of RM Sotheby’s.
Herb Jordan spent his working life as a machinist, tool maker, and later, engineer for IBM Canada. An inventor by nature, Jordan built everything from a rotary valve motorcycle engine, loosely based upon a 1931 AJS 350cc single, to a Formula 3 race car of his own design. Later, as a member of the Toronto Society of Model Engineers, Jordan would turn his attention to building functional scale models of significant Porsche racing engines, and on December 10 a pair of his models will be heading to auction in New York City.
In the world of scale models, functional can take on many different meanings. Some scale engines are stunningly accurate representations of the real thing, down to the script on the valve covers, and contain precisely rendered moving parts. Some are designed to be “powered” by compressed air, while a smaller percentage yet are built to be started and run, perhaps the ultimate testament to a model-builder’s skill. Jordan’s engines fall into this latter category, and while they may not be exact scale duplicates of the original, their functional intricacy is stunning.
Carrera Four-Cam engine scale model.
Jordan chose Porsche’s Carrera Four-Cam engine for his first working model, constructed over two years (and 2,000 hours) in the early 1970s. The actual Porsche engine was produced in a series of displacements ranging from 1,500 cc to 2,000 cc, and Jordan’s 1/3 scale model most closely resembles the later 2.0-liter variant. With a bore of 1-inch and stroke of 0.875-inch, the 12-inch long model displaces 42 cc and was designed to run on methanol.
Working with a 10-inch lathe, a milling machine, a shaper, a drill press, and hand tools, Jordan machined all the key components on his own without resorting to casting. The aluminum block uses iron cylinder liners for durability, and the scale Weber IDA downdraft carburetors were assembled from over 50 individual brass components. The chain-driven cams run on needle bearings, and like the full-size engine, the cylinders are finned to dissipate heat.
By the dawn of the 1980s, Jordan was ready for a new challenge, and turned his attention to an engine that’s among the Stuttgart automaker’s most legendary: the twin-turbo flat-twelve used in the later model open-cockpit Porsche 917s. In full-size form, the complex 5.4-liter engine produced as much as 1,500 horsepower in its final variants, while even early 4.5-liter forced induction versions made a minimum of 800 horsepower.
Jordan’s 917 engine on its “test bench.”
Building on the experience gained from crafting his original Porsche engine, Jordan again manufactured the engine’s individual components by hand. Like the full-size variant, his model uses gear-driven mechanical fuel injection and gear-driven overhead camshafts, spun from gears mounted in the center of the engine block. While Jordan’s Carrera four-cam engine could spin to a redline of 20,000 RPM, the 917 engine was capable of achieving a truly remarkable 24,000 RPM, albeit for short bursts. Even the twin turbochargers were said to be functional, with the engine’s builder rating output as “more than sufficient.”
Jordan reportedly labored for four years in crafting his ¼ scale 917 engine, which displaces 54 cc; measures 15-inches long, eight-inches wide and seven-inches tall; and weighs in at roughly 15 pounds. Upon completion in 1984, the engine was run frequently for demonstration purposes, and both models were regularly displayed at meetings of the Toronto Society of Model Engineers.
As described in the catalog, the Carrera four-cam engine hasn’t run in nearly 30 years, and its larger 12-cylinder brother hasn’t operated in “some time.” At a minimum, a thorough tear-down and inspection of both will be necessary before they’re brought back to life, assuming, of course, that the buyer isn’t content to admire the engines in static form.
It’s difficult to put an exact value on handcrafted scale art such as this, but RM Sotheby’s predicts a selling price between $20,000 and $40,000 for each of Jordan’s engines, and the Carrera four-cam model is being offered at no reserve. For complete information on the Driven by Disruption sale, visit RMSothebys.com.
from Hemmings Daily - News for the collector car enthusiast http://ift.tt/1MxovQ3
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