Ford flathead V8 engine
The Ford flathead V8 is a V8 engine with a flat cylinder head introduced by the Ford Motor Company in 1932 and built by Ford through 1953. During the engine's first decade of production, when overhead-valve engines were used by only a small minority of makes, it was usually known simply as the Ford V‑8, and the first car model in which it was installed, the Model 18, was often called simply the "Ford V-8" after its new engine.
An automotive milestone as the first affordable V8, it ranks as one of the company's most important developments. The engine was intended to be used for big passenger cars and trucks; it was installed in such until 1953, making the engine's 21-year production run for the U.S. consumer market longer than the 19-year run of the Ford Model T engine. It was also built independently by Ford licensees..
The Ford flathead V8 was named on Ward's list of the 10 best engines of the 20th century. It was a staple of hot rodders in the 1950s, and it remains famous in the classic car hobbies even today, despite the huge variety of other popular V8s that followed.
Development and production
Ford had helped pioneer the concept of an affordable mass-produced car. Historically, these used inline-four and inline-six cylinder engines. Following French engineer Léon Levavasseur's invention of the V8 in 1902, V8s, V12s, and even V16s, were produced for use in luxury models. The Cadillac V8 engine is credited as the first mass-produced V8, and when Ford Motor Company acquired rival luxury marque Lincoln in 1922, the maker was already producing a flathead V8 with fork and blade connecting rods, which remained in production after Ford took over until 1932.Even though Ford had an engineering team assigned to develop its own V8, many of the ideas and innovations were Henry Ford's. The Model A, its variants, and this V8 engine were developed between 1926 and 1932, and this period was the elder Ford's last central contribution to the company's engineering.
Mercury's version of the engine was introduced in 1939.
An economizing design feature of this engine was the use of three main bearings to support the crankshaft, rather than the customary five used with most V-8s. The flathead mounted the camshaft above the crankshaft, like later pushrod-operated overhead-valve engines. Valves for each bank were mounted inside the triangular area formed by the "vee" of cylinders. The intake manifold fed both banks from inside the vee, but the exhaust ports had to pass between the cylinders to reach the outboard exhaust manifolds, since it did not use a t-head configuration. Such an arrangement transferred exhaust heat to the block, imposing a large cooling load; it required far more coolant and radiator capacity than equivalent overhead-valve V8 engines. Ford flathead V8s were notorious for cracking blocks if their barely adequate cooling systems were overtaxed. The simple design left much room for improvement, and the power available after even low cost modifications was usually substantially more than could be obtained from an overhead-valve inline six-cylinder engine of similar displacement.
The Ford flathead V was manufactured in several countries other than US, including France, Australia, Germany and Sweden.
The Ford flathead V8 was licensed to other producers. It was used by Simca in France until 1961 and in Brazil until 1964 for cars and until 1990 in the Simca Unic Marmon Bocquet military truck. In the United States, the flathead V8 was replaced by the more modern overhead-valve Ford Y-block engine in 1954. During World War II, the engine was used on the first prototype of the Romanian Mareșal tank destroyer, but was considered too weak and thus replaced by more powerful engines for later versions of the vehicle.
Components
Crankshaft
The crankshaft development for the Ford flathead V8 was pioneering. The engine's production development program began with a forged steel crank, per conventional practice, but Ford then developed the improved foundry practice, heat-treating, and materials handling logistics to make the cranks from cast steel instead, yielding a crank just as strong, but less expensive to produce. These new methods were patented. The simple three-main-bearing crankshaft attached two connecting rods to a single crankpin, one rod from each cylinder bank. As with other crankshafts, static and dynamic balancing was performed.The short crankshaft proved quite durable in comparison to six-cylinder engines when roughly handled. For these reasons, the flathead Ford became a favorite among hot-rodders, and this in turn led to a rich supply of aftermarket performance parts. With the use of specialized pistons or connecting rods the stroke of the crankshaft could be increased by welding and regrinding as a method of increasing engine displacement, usually in combination with overboring.
Block
One of the most important innovations in the Ford flathead V8 was the casting of the crankcase and all 8 cylinders in one engine block. This level of monobloc design for V-8 blocks had been accomplished before, but it had never seen mass production. Making it practical for the latter was an example of the production development needed to bring a V8 engine to the widely affordable segment of the market. Most V engines of the time had multiple cylinder blocks bolted to a common crankcase. At most, each bank of the V was an integral block, but many V engines had four- or even six-cylinder blocks, with cylinders cast in pairs or triples. Like most other engine blocks of the 20th century, it was cast iron; but the foundry practice was a revolutionary advancement in the mass production of castings. Charles E. Sorensen lived up to his longtime nickname at Ford, "Cast-Iron Charlie", by leading this revolution to bring Ford's first V8 to market.As with any V8, the block was relatively light for the displacement supported. The cooling jacket reaches down to the bottom dead center, which is unusually low. American engineers at the time believed this would improve the piston cooling. The bottom of the block formed the parting line for the main bearing caps. The most complex part of the block was the exhaust passage routing. The exhaust valves were on the inside of the V and exhaust flow was initially downward and passed around the cylinders through the water jacket to exit on the outside of the cylinder block. The routing of the exhaust through the water jacket put an extremely heavy load on the cooling system and led to frequent overheating, especially on early models, if the cooling system was not maintained. Somewhat primitive water pumps used until the advent of the 1948 8RT and 1949 8BA models also contributed to the overheating problem. The space for the exhaust flow was also somewhat restricted, so the exhaust passages were tall and narrow in some locations. The gas flow past the rough sand castings could be greatly improved by polishing the passages. In early blocks, some cylinder walls were extremely thin due to cores shifting during casting.
Bearings
The engines built from 1932 to 1935 had poured main bearings which required skill and machine shop equipment to overhaul. Part of the 1936 production and all production from 1937 to the end of flathead V8 production had both replaceable shell main bearings and connecting rod inserts, enabling straightforward and low cost rebuilding, another reason why the Ford was a favorite of amateur mechanics. These shell main bearings are made of a cadmium silver alloy.Camshaft and timing
The Ford flathead V8 has a single camshaft located inside the engine block above the crankshaft. It is spur gear driven; the camshaft's spur gear is made of plastic. The camshaft has three camshaft bearings. A lid made of cast iron covers the camshaft spur gears; the ignition distributor is placed on top of this lid and is driven by the camshaft spur gears. For powering the fuel pump, the camshaft is fitted with an extra cam located in the bearing on the flywheel side.Lubrication
Ford products used high oil pressure for lubrication for the main and rod bearings, as do all modern vehicle combustion engines. This offered a significant performance advantage, as full pressure lubrication allowed for continuous use above 3500 rpm and would not starve the rod bearings for oil, which was necessary for high performance applications, such as racing. For this reason, bank robber Clyde Barrow preferred to steal Fords as getaway vehicles. It also eliminated a complex oil jet system to feed the rod bearings in the oil pan. As a side benefit to a prospective purchaser of a used vehicle, this also enabled the condition of the connecting rod and main bearings to be determined indirectly by observation of the oil pressure gauge after the vehicle was warmed up, provided that oil of normal viscosity was in use.Exhaust
The exhaust outlets in the 1932-48 cars and the 1932-47 trucks were near the front of the manifolds aiming down and sometimes out. A Y-pipe took the exhaust gases to the right side of the vehicle to a single muffler, then to a single pipe out the back on the right side. The left side exhaust manifold exhausted to the front in the 1949–53 Ford cars, where a crossover pipe took the exhaust to the forward end of the right side manifold on the car engines and between the 1st and second cylinder on some trucks, in turn exhausting to a single pipe at the rear.A common conversion for the 1949-53 Ford cars and 1952-53 Mercurys was to block off the right forward manifold entrance and route the left side exhaust to a new pipe to form a dual exhaust system with better flow characteristics. These typically involved installation of free-flowing mufflers, which if at a legal noise level still allowed low frequency sounds to pass, giving a characteristic rumbling dual exhaust sound to these systems. In the 1950s shortcut exhaust outlets with manually removed covers were added to street machines in emulation of vehicles intended for high speed straight line racing on dry lake beds, typically located just behind the front wheel, although chromed external runners sometimes extended to just forward of the rear wheel. These covers were referred to as lake plugs, the pipes as lake pipes. This style exhaust was also used legally in sanctioned drag racing and illegally in unsanctioned performance demonstrations.