Famous Engines

Henry Ford’s 2-cylinder engine in Sweepstakes

April 15, 2011

Ford Sweepstakes engine 2-cylinderWhen Henry Ford began building “Sweepstakes” race car in 1901, he had a specific purpose in mind: publicity and recognition. Racing proved the worth of a builder’s engineering talent by demonstrating the speed and reliability of the product. In the Sweepstakes race car the engine was mounted in the middle of the car on the left-hand side, under the seat. It had two cylinders, horizontally opposed, with the crankshaft aligned transversely across the chassis. The cast-steel connecting rods reflected steam-power technology, with brass crank bearings as separate pieces bolted to the ends of the rods. The block and pistons were cast iron and with a seven-inch bore and seven-inch stroke, the total displacement was 539 cubic inches.

The cooling system holded eight gallons of water, circulated by a pump located on the outboard side of the engine. The pump was driven by a chain from a gear on the outboard end of the crankshaft. The fuel tank holded approximately five gallons of gasoline, fed to the engine by gravity. The engine oiling system was simply a series of drip mechanisms that delivered oil to the desired locations. Since the crankshaft spinned in the open, a lot of oil was thrown around when the engine was running, soon covering not only many external parts of the car, but also the driver and riding mechanic. This was called a “total-loss” oiling system, because none of the oil was recovered or recirculated.

The cast-iron flywheel, mounted on the inboard end of the crankshaft, measured 24 inches in diameter and weighted 300 pounds. A secondary wheel, fitted into a flange machined into the inside of the flywheel’s rim, acted as the high-gear clutch. Next to the high-gear clutch was the two-speed planetary transmission, with a first-gear band and a reverse band. A sprocket, mounted at the center line of the car, carried the drive chain, which ran to another sprocket on the differential in the rear axle.

Several elements in the car were innovative and technologically advanced for the time. The induction system, then called a “vaporizer,” was a rudimentary form of mechanical fuel injection, throttled by varying the amount of intake valve opening. The ignition system was a forerunner of today’s distributorless coil-on-plug systems. It is called a “wasted-spark” system, because the spark fires on both the compression and the exhaust strokes. Both the vaporizer and the spark coil system were patented by Ford.

The “Huff” ignition system was innovative because it had porcelain insulators on the spark plugs. Spark plug fouling was prevalent in those early engines, so Ford and his team engaged the services of a Detroit dentist, Dr. W. E. Sandborn, to make ceramic insulators for their plugs. The electrical insulation gave a hotter, more consistent spark. In fact, after the 1901 race Alexander Winton bought several of Ford’s spark coil systems for his cars.