Flathead Ford V8

In December of 1931, in the midst of America's Great Depression, Ford Motor Company stopped production of their four-cylinder engine and began manufacturing a new flathead V8. Unlike V8's of the day (Cadillac, LaSalle, Lincoln) which the engine block and crankcase were bolted together, Ford designed a one-piece casting with bolt-on exhaust manifolds. The 90-degree, L-head, side-valve V8 used a 0.265" offset crankshaft for reducing piston slap, which made for a smoother running lower end. Henry Ford wanted an over-square motor, but the flathead V8 would always be under-square.

Flathead Ford V8

Advantages of a flathead (side-valve) engine over an overhead valve engine were cost of manufacture and simplicity. With valves positioned in the engine block beside the piston (instead of in the cylinder head, as in an OHV engine), push-rods and rocker arms were not needed. Additionally, cylinder heads need only be a simple casting with threaded holes for the spark plugs.

1932-1938 Ford Flathead V8

The first-design flathead Ford V8 engines had 21 cylinder-head studs and are known as "21 stud" motors. Until mid 1936, poured Babbit main-bearings were used. The bell housing was cast into the back of the block, These early blocks are hard to upgrade but are highly prized by collector car restorers.

early Ford Flathead V8

Several issues plagued the early Ford flathead blocks, including overheating, casting porosity and cracking near the valve ports. Early flathead Ford V8 water pumps were actually Model A units, designed to fit the new engine to save cost and retooling.

1933 Ford Sedan

Most easily recognized by the two water pumps mounted to the front of the heads, production of the original 221ci Ford flathead ran from 1932 to 1936. A smaller 136ci V8 engine was also produced from 1937-1939.

Ford Flathead V8

An updated design in 1937 had the water outlets relocated from the front of the heads to the top center of the heads. These were produced in 1937 and early 1938.

1938-1948 Ford Flathead V8

Needing a more powerful motor for their new Mercury line of cars, Ford introduced the 239ci "24 stud" engine (twenty-four studs holding down each cylinder head) in late 1938. Producing 95-horsepower and 170 lb/ft of torque, these engines were used through 1942 for civilian use and also World War Two military vehicles. These second-design blocks (often referred to as 59A castings) retained the integral cast-in bell housing,

Ford Flathead parts

Find Ford Flathead Parts At Mac's Auto Parts

The 1939-1948 Ford flatheads had insert-style main bearings, but still used full-floating rod bearings (one bearing shell for each rod pair). A direct camshaft-driven front-mount distributor mounted flush to the cover, with a horizontal shaft on the front of the engine.

Ford Flathead History

1949-1953 Ford Flathead V8

The third-design "8BA" engines (8RT for Ford trucks) were produced from 1949 to 1953. The block itself was the same for both Ford and Mercury, and had a higher 6.8:1 compression and bolt-on bell housing. The 24 studs and nuts that attached the heads on the block were replaced by 24 bolts, and left and right heads had different gaskets.

1949 Ford convertible

A revised cooling system had the water inlets and thermostat housings moved to the front end of the heads. The gear-driven distributor was now vertically mounted on the right-front of the engine. Early and late distributor styles can be interchanged by using the corresponding front engine covers and cam drive.

1948 Ford F1 pickup

Flathead V8 motors were available in 1948-1952 Ford "Bonus-Built" Trucks.

The End of Flathead Production

After 22 years in production, Ford's venerable flathead V-8 was discontinued. In it's place was a new overhead-valve V-8, displacing the same 239 cubic-inches as the flathead by way of an over-square 3.50" bore by 3.10" stroke. Power output was 130-horsepower, an increase of 15% over the flathead's 106-horsepower.

After 1953, flathead production continued in other countries. The Ford Flathead V8 engine continued to be used in French military vehicles through the 1990s, with a good supply of new flatheads still available.

Flathead Ford Legacy

The engine's 21-year production is on "Ward's List of the Ten Best engines of the 20th century". From 1932 until 1953, the Ford Flathead V8 was placed in over 25 million cars and trucks. The Beach Boys immortalized the flathead in their 1964 hit single, "Little Deuce Coupe."

Old Woodie Wagon at classic car show

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