HomeGarageHere's why Ford killed its flathead V8 engine 65 years ago

Here’s why Ford killed its flathead V8 engine 65 years ago


Ford’s famed flathead V8 was revolutionary when the automaker put the engine into production in 1932. It brought the V8 to the mass market and ready power to hot rodders for decades to come.

But its design would eventually make it outdated. After more than two decades of service, the flathead V8 was finally laid to rest more than 60 years ago in favor of an overhead-valve design. 

Why did Ford kill the innovative V8 engine? That’s a job for Jason Fenske of Engineering Explained to expound upon. Using a 3D-printed model for a visual aid, Jason takes the time to walk us through why the engine was so advanced, but also the downfalls that led to its death.

Ford’s design was incredibly simple, which made the engine cost-effective to produce. Its simplicity and affordability also meant an everyday person could purchase a V8-powered car.

The first flathead V8 displaced 3.6 liters and boasted a compression ratio of just 5.5:1. It put out 65 horsepower in the 1932 Ford Model 18, a major selling point at the time.

As you can see from Jason’s model, the flathead engine design features rather flat heads, which is how the mill earned its nickname. Each head is a single piece of metal that helped keep costs much lower. A single camshaft sits in the center of the block’s V, and the exhaust and intake valves are situated above each piston.

So, why did the revolutionary V8 die off? Advances in technology is the overarching answer, but it came down to the flathead’s major airflow problems and low compression ratios.

As you can see in the video, the airflow path for the engine is hardly ideal. As the air feeds its way through the engine, it has to turn 90 degrees, then turn another 90 degrees to head into the cylinder. A modern engine’s valves help route air toward the piston, around it, and then down into the cylinder.

When air comes back up from the cylinder, it has to perform the same 90-degree turns, now in the opposite direction. Add in the fact that the intake and exhaust flow sit in opposite directions, and it’s easy to see why the flathead V8 wasn’t an efficient engine.

Engineers couldn’t simply open the intake and exhaust valves open more, either. That would have meant digging out more area in the cylinder head, which would have lowered the already low compression ratios further.

In 1953, Ford made the final flathead V8. It displaced 3.9 liters and made 110 horsepower. As engineers sought more power, Ford scrapped the design in favor of an overhead-valve engine. Thus the flathead V8’s tenure came to end.


  1. Also, after you spend months building a 315 cubic inch (that’s 5 liters) flathead in your garage with all the goodies that Hot Rod Magazine recommends to create a big chugger, bring it to the drag strip and get blown off by a 55 Chevy that some guy just rolled out of the show room, you tend to start thinking about getting rid of your flathead and looking for a new Chevy.

    • I have a 53 Mercury Flathead bolted to a Bronco 3 speed manual overdrive tranny in my 32 Ford pickup that I use to pull around a vintage 2-wheel trailer hauling an early 50s Flathead slingshot. Neither engine races anymore but they are “cackelfest” favorites. 14 years of fun so far.

  2. Flathead Ford engines were made at least through 1966 in Canada. South America and Australia had flathead engines into the 1960s.

  3. The French military used the Ford flathead V8 into the mid 1990’s. It was a hibrid casting of the 8ba (49-53) with the 59ab. (39-48) bell housing cast into it. Under license from Ford, They improved the cooling passages and had French car maker Simca cast them in high nickel steel to prevent cracks, instead of cast iron (like Henry did it) I bought one in cosmoline unused standard bore,and it bolted right into my 39 fire truck


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