As the flathead V8 era at Ford was drawing to a close, the carmaker introduced a super-sized version of the venerable flathead to power its Lincolns and big Ford trucks.

Introduced in 1932, the famed Ford flathead V8 had a long and successful production life, but by the late 1940s its limitations were all too evident, especially in heavy trucks. Even before World War II the company was working on replacements, including an overhead-cam V8 with an aluminum block that didn’t make the cut. Ultimately, the company decided on a larger version of the familiar L-head V8 that would be suitable for trucks and for Lincoln as well, as the Zephyr V12 was due for retirement. (More on the Zephyr V12 here).

With a bore of 3.50 inches, a stroke of 4.375 inches, and a displacement of 336.74 cubic inches, the new V8 was very much the familiar Ford flathead, only bigger. Much bigger—fully dressed, its weight was listed at nearly 850 lbs. But the 337 featured three main bearings on the crankshaft and twin water pumps, just like the original, and the same 15486372 firing order.

However, there were some important differences, too. The cylinder heads (all were cast iron) were secured to the block with 27 studs each rather than 24 or 21. The crankshaft was forged, not cast as with the standard flathead, while the rod journals were a husky 2.40 inches in diameter. Intake ports were more generous, feeding larger 1.81 intake valves. Most obviously, the distributor was mounted at the top rear of the engine, an improvement over the awkward and difficult front location of the smaller V8. It’s an easy way to distinguish the 337 from the other flathead V8s—not that folks have much trouble telling them apart due to the 337’s greater size.

1949 Ford F-8

The big V8 made its first appearance in January of 1948 on the F7 and F8 “Big Job” trucks, Ford’s heaviest haulers, and in the 1949 Lincoln for its debut on April 22, 1948. The truck and passenger car engines are essentially the same except for their accessory dress and other details. Lincoln versions all featured hydraulic lifters, while most trucks used mechanical followers. And while the truck V8 was rated at 145 hp, the Lincoln offered 152 hp at 3,600 rpm, which was bumped to 154 hp and 275 lb-ft ot torque at just 1,800 rpm for 1951. Coupled to Lincolin’s optional GM Hydra-Matic transmission, the big flathead was a sound and smooth performer.

1951 Lincoln Cosmopolitan

Despite its apparent performance potential, hot rodders never really embraced the plus-sized flathead as they did with the original, no doubt due to its formidable size and weight. Few speed parts were manufactured, mainly aluminum high-compression cylinder heads and multiple-carb manifolds. While the massive block could easily  accommodate displacements of 370 cubic inches or more, there were very few takers.

In retrospect, the 337 CID V8 was a stopgap solution—its days were numbered from its introduction, though it continued in production through 1951, turning in a  respectable performance. Far more modern overhead-valve V8s were already arriving on the scene with short strokes and higher compression, starting with Cadillac and Oldsmobile. For 1952, the Ford Motor Company introduced its own overhead-valve V8 for Lincoln and Ford trucks, and you can read about it here. 

1950 Lincoln Cosmpolitan Sport Sedan