The Ford Flathead V8 is arguably the most famous engine in hot rodding history.
Introduced in 1932, Ford used it in U.S. passenger cars and trucks until 1953. Its popularity with hot rodders started almost immediately, and amazingly is still going strong today, almost 90 years later.
The V8 had been invented in France in 1902, but early V configuration engines (V8s, V12s, and V16s) were used almost exclusively in expensive, limited production cars. It should be of no surprise that it was Henry Ford who wanted to bring the power of the V8 to the average car buyer.
The Flathead made its first appearance in the 1932 Ford Model 18, checking in at 221 cubic inches. With a single barrel carburetor and 5.5:1 compression ratio, it chugged out 65 horsepower. (The 1934 Model 18 is the one Clyde Barrow, of Bonnie and Clyde bank robber fame, supposedly wrote a letter to Henry Ford about. Apparently the Flathead made for a great getaway vehicle.)
The key to making the engine affordable was keeping it simple. Having the valves mounted in the block just above the piston bores made the cylinder heads essentially just a flat slab of steel – which is how the engine got its nickname. Ford made the entire engine block out of one casting, which was not common for V-configuration engines at that time. And the crankshaft was supported by just three main main bearings.
But the simplicity also limited power and efficiency. One of the main problems was that the airflow in and out of the cylinders had to follow a very restrictive path.
So you had a simple, relatively inexpensive engine that needed to be tweaked a little bit to perform better. That’s a perfect job for hot rodders.
All the usual hot rodding tricks worked perfectly on the Flathead: porting and relieving the intake and exhaust ports; smoothing the combustion chambers in the cylinder head; boring out the cylinders; increasing the crank stroke. More airflow and more cubic inches equaled more horsepower, just as expected.
And when you get an engine to produce more horsepower, it always ends up on the drag strip the next weekend. The Flathead was a staple on the quarter-mile, with carbureted, fuel injected, and blown versions powering everything from gassers to rail dragsters. It’s still popular today on the nostalgia drag racing circuits.
The hot rod modifications helped, but eventually they ran up against the Flathead’s inherent design limitations. The laws of physics decreed that overhead valve V8s would produce more power, and as the OHV engines became more ubiquitous, they quickly became the go-to choice for hot rodding and racing.
Famous it may be, but I’d never seen a Flathead motor in person until this month’s Georgia Street Rod Association meeting, where there were three of them between the members’ cars and the ones on display at Sparky’s Machine.
There are more powerful engines you can put in a rod, but nothing beats the look, or generates the nostalgia, of a Ford Flathead. It’ll be approaching its 90th birthday soon, but I suspect it’ll still be around for a long time to come.