Feuling holds more than 100 patents in the automotive industry, with R&D; contracts with companies such as Cheverolet, Oldsmobile, Ford, Chrysler, Nissan, John Deere, and Harley-Davidson. He developed four-valve heads for Harley-Davidsons and later sold the rights to Ultra Cycles. He also designed an engine for American Honda's high-mileage streamliner that delivered a whopping 500 mpg at 55 mph. He holds several land speed records, including one for a motorcycle streamliner at 333.847 mph set on the Bonneville Salt Flats on October 20th, 1999. Feuling R&D;'s 28,000-square-foot facility is chock full of CAD/CAM/CAE machinery, making the company one of the few private facilities in the world that can design, test, and build entire vehicles (including the engine and drivetrain) under one roof. The W3 engine project initially began in conjunction with Harley-Davidson, but as the design reached the end of the initial stages, Harley opted out. With the withdrawal of Harley-Davidson, Feuling went back to the drawing board. The original design had been structured so that H-D would need to add just six new part numbers to its inventory. When Harley opted out, that concern was scrapped in favor of a design that used only parts available in the aftermarket plus a few application-specific items that could be manufactured by Feuling.