alt="In 1942, the coil ..."/>
The 24-stud, 221-ci Ford engines from 1938 and on have just two head bolts in the center; some say they form an inverted Y. Being newer engines, they are somewhat preferable to those of previous generations. The contemporary Merc engine had 239 cubes courtesy of a slightly larger, 3.1875-inch bore.
In 1942, the coil was finally separated from the distributor, which was mounted through the side of the front cover.
For 1937–1941, the distributor was held on with two bolts, rather than three, and the coil is taller.
The 1932 pumps had high water necks. From 1933 to 1936, they had lower necks (shown).
External Clues
Heads: A quick way to separate a pre-1938, 21-stud engine from a 1938-on 24-stud engine is to look at the middle row of head studs.
Coil and Distributor: The 1932 V-8 had its distributor mounted directly on the front of the camshaft and was identified by its tall, integrated coil that necessitated a long fan shaft. From 1933 to 1936, the tall integral coil was shorter; late in 1936, it used a flattop coil.
Water Pump: Over its life, the flathead, in its various guises for cars, trucks, and so on, had numerous different water pumps; their configurations can be a helpful guide in identification. From 1932 until 1936, the water pump was located at the front of each head, although the 1932 pump had a high water neck.
In 1937, the water pump moved from the head to the front of the block, with the upper radiator hose attached to an outlet at the top center of the head. In 1949, the water neck became a thermostat housing and was bolted onto the front of the head.
Internal Clues
As mentioned in Chapter 1, Henry Ford, who apparently could hardly read a blueprint, dictated that his V-8 have a thermosyphon cooling system, stating, “Thermostats are crummy.” He also demanded a fuel pump atop the engine, where it literally sucked more than it pushed, causing vapor locks. Water vapor was also forced into the pump from the crankcase, causing corrosion and even freezing in cold weather, sometimes stopping the pump. It had no oil filtering system, and the ignition system was inadequate. Adjusting the points involved removing the distributor from the engine and putting it on a test rig, or replacing it. Consequently, the public became lab rats, testing the engine as it underwent constant development to improve reliability and performance.
The 8RT series pumps were used in truck and commercial applications from 1948 to 1952. They all had wide-belt pulleys.
The 8CM series wide-belt pulley was fitted to the 1949 Mercury, while the narrow-belt OCM was fitted to 1950–1951 Mercs.
The 8BA water pumps were fitted in 1949–1953 cars, 1953 Ford trucks, and 1952–1953 Mercurys. Both wide and narrow belt pulleys were used.
If you have a box of rods and need to identify them, here’s a selection. From left to right: 21-stud, 59A, 8BA, and new Scat. If you’re lucky, the rods will be marked, as is the 8BA, but quite often there are no identifying marks.
Because the flathead V-8 underwent so many minor changes, we endeavor here to visually explain the running block changes from the second-generation 1933 engine through the final 1949–1953 version. The 1932 engine is not included because it is rare and now used only in the most precise restorations.
Some of the changes are quite obvious. These include the 1937 relocation of the water pump to the front of the block, the 1938 shift from 21-stud heads to 24-stud heads, and the 1949 introduction of the conventional and more vertical (rather than front-mounted) distributor.
Crank: Identifying cranks is no longer necessary because Scat introduced brand-new cranks. Previously, everybody searched for 4-inch-stroke Mercury cranks. To determine which crank you have, use the “pinky or pencil” test: If your pinky fits, it’s a Merc; if a pencil fits, it’s a Ford.
Rods: The original factory Ford rods were heat-treated, carbon manganese steel forgings and were as good as it gets. If the ones you have are not bent, twisted, or cracked, they are ideal for a street or mild performance rebuild. If you are building a more high-performance or racing engine, I suggest new H-beam chrome-moly high-tensile forged rods from Scat. Scat also offers different crank pin sizes: 2.000 and 2.138 inches, available with either studs or cap screws.
Block Identification
1933-1936½
The 1933–1936½ block was a 21-stud, identified by three head studs on either side of the triangulated water passages. It also had a cast-in bellhousing.
Water pumps on 1933–1936½ blocks were located at the front of each cylinder head. The upper portion of the front of the block was smooth.
The 1932–1936, blocks had poured, white-metal Babbitt main bearings. The conventional insert bearing option was introduced in October 1935. Both the poured (meaning that the white-metal bearing material was literally poured into the rod and cap) and the conventional insert styles were available through 1936. This is a Babbitt block.
1936½
The late 1936 engines are desirable 21-studders, still with the triangulated water passages and integrated bellhousing, but they are really preferable because of the insert
