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OK, so to start, just what is a flathead? Well, every time you go out to start up your Briggs & Stratton lawnmower engine, you're firing up one.
A Flathead is an engine in which the valve is in the block, not in the head, in what is called an 'L' configuration or layout. It is one of the
earliest valve configurations for the internal combustion engine and was favored at the inception of such devices for its simplicity and lower manufacturing cost. It has to be pointed out though that by the time the spectacle of
racing had permeated the social conscious, both here in America and abroad, the OHV (Overhead valve) engine was king. Conversions for the flathead 4-Cylinder engines of the early teens were quickly produced for any and all racing events, often (but not always) leaving their flathead brothers in the dust. The problem with these early OHV conversions, as well as the early OEM (Original Equipment Manufacturers) overhead valve arrangements was their cost, even though they were available, not everyone could afford one.
Henry Ford was as much genius as he was visionary. After two failed attempts in the auto industry, he came up with his two winners: the assembly line and an affordable motor car for the masses - the Model T. The assembly line
was to become the model for modern manufacturing; interchangeable parts greatly reduced the cost of manufacture allowing nearly all to crank over the “Any color you want so long as it's black” Model T's. As much as
he wanted to put everyone in America in a car, he also wanted everyone to be able to enjoy the smooth power of a V8 engine.
In the 1920's these engines were available only to the privileged who could afford them. They rested in hulky luxury cars of the time and were often of a 'modular' design, which basically meant that they were costly to manufacture and maintain. After his successful run of the Model T was over in 1927, Henry offered the public his upgrade - the Model A but still used the same
basic flathead 4 engine layout. He then turned his engineer’s attention to developing an affordable V8 and in 1928 the thrash began. By 1932 the engineering and tooling of the new flathead V8 was complete and introduced mid-year to the public. For it's time, it was an
engineering marvel, the intricately cast block is still a testament to the skill of those who created it. Public response was fantastic, the engine was a considerable upgrade over the 4 cylinders of the time, doubling the horsepower from 40 to 80 and the cars were some of the
fastest of their day. As has been well documented, bank robbers such as Clyde Barrow and moonshiners preferred the light Ford cars for their speed and dependability.
The engines remained viable through the 1930's, 1940's and up until 1953 in America (1954 in Canada, and were also cast up until approx. 1991 in France for military use). Which means that there were a lot of these engine cast and sold. The true death knoll for the Flathead V8 was in
1949 when Cadillac introduced their OHV V8 to the public, again a sizeable upgrade in power which the flathead could not match. For the racers and hotrodders of the 1950's the true end of the Flathead era came in 1955 when Chevrolet introduced it's small block OHV V8. Virtually the same size and weight with twice the horsepower, it was the obvious choice to supplant the faithful flathead, and remains so to this day.
For this discussion though, we're going to concentrate on the racing flathead of the 1950's and 1960's and the equipment and modifications which racers applied to the engine. Specifications, history, technical advice, etc. is readily available through either books or the web and we'll provide links to that information for those interested.
Allright - so why a Flathead for the racers of the time? There are several reasons the first of which is availability. When first introduced, most racers shunned the engine in favor of their tried and true 4 bangers with which they had much experience, and equipment. It's interesting to point out that later automotive manufacturers like Arthur and Louis Chevrolet started by making OHV conversions (in this instance, the Frontenac head) for the Ford 4 bangers. With time though came acceptance of the Flathead V8 and it's true potential was unlocked by
moonshiners in the south. These moonshiners would congregate in fields on Sundays to test one another in front of small crowds, pass the hat for a winners share and compete. Thus stock car racing was born.
Once the potential of these events was realized by the promoters of this time and organization came into play, the spectacle of Stock Car Racing permeated the general public’s awareness and took off at dusty county horse tracks across America. It reached upstate NY in approximately
1948 and has been here ever since. By that time, flathead V8's were more than plentiful and thus cheap. Mechanics were experienced with them and due to their simple design; nearly anyone with a set of wrenches could work on one. Also, due to the ever burgeoning hot rod and speed trial movements on the West Coast, and the fact that many young energetic men had returned from the
WWII effort with money in hand and a need for speed, the sport took off.
The West Coast (and California in particular) offered manufacturing opportunities after the
war effort was complete. Aluminum was again available and casting techniques had improved immensely. Hot Rodders and race car owners like Vic Edelbrock, Earl Evans and Barney Navarro started offering their heads and intakes that they had proven at the dry lakes and
race tracks, and their businesses took off. In essence, the Flathead V8 is where it all started for both Hot Rodding and Stock Car Racing.
OK, so those were the advantages of having a flathead as far as the racers were concerned-
availability of equipment and cost, what were the disadvantages? Ford originally designed the Flathead V8 for everyday driving and rated their engines at anywhere's from 80 to 115 Hp @ a modest 3600 RPM during its production run.
They were meant to give consumers quick starts,
reasonable power and torque as well as reliability over their service life. In other words, they weren't designed for
racing and as such had many drawbacks which racers had to overcome as they tried to coax nearly double the horsepower out of them in racing trim. The first problem was the 'L' head valve configuration which creates a torturous path for the air fuel mixture making it's way
into the combustion chamber. Although adrawback, it's also one of the flatheads few advantages in that the mixture is so well atomized by the time it's compressed, very little ignition lead (as compared to the OHV V8) is required. The downfall of this arrangement is that it's
more difficult to get the charge into the combustion chamber than in an overhead valve engine. You've undoubtedly heard the phrase; “You can't beat cubic inches” and it's true. More cubic inches equals more fuel -
air mixture which means more power can be created. It's a bigger bomb.
Next problem for the Flathead V8 is
getting the spent charge out. Many have asked us “why only three exhaust headers?” and the reason is that the center two cylinders on each bank of the engine share a
siamesed exhaust port. This was most likely done for ease of casting and cost but it doesn't help in the performance of the engine. Not only does it create some constipation but also is a very efficient way of heating up the engine
coolant and all Flathead V8's have a well earned
reputation as boilers.
Now, let's look at the bottom end of
the engine and note that the V8 retained its brother 4 banger's crankshaft main layout which equal three. Fine for 100 horsepower but no comparison to the five mains of an overhead V8 or the seven of later 6 cylinder engines.
The crankshaft of the Flathead V8 weighs in at a hefty 68 lbs. while the rods are seven inches long and though a rugged 'I' beam design - they are at best described as spindly and light (another advantage?). There's more but that's probably enough for now. So, how did the racers combat these problems? Mostly by cut and try.
Link over to the Midstate Antique Website for more...BRONCO
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