Use dividers or, preferably, a micrometer to measure the bores. There’s no sign of sleeves, so this might be a good candidate.
A Vernier gauge or a ruler tells you the bore size. Stock for the 8BA is 3.1875 (3) inches. The maximum recommended overbore is 5/16 inch, so there is some meat left here.
First Look
To begin, remove both cylinder heads and wire brush the deck to check for obvious cracks. Also inspect near the pan rail for signs of freeze cracking. The more care you take looking for cracks, the better you’ll be in the long run. If obvious faults frighten you, pass on the purchase.
Bellhousing or No?
If the block/engine looks worth buying, you should probably decide (yes, this early in the game) what transmission you will run, as this will make a difference in the choice of block. For example, the 1949–1953 blocks without the integral bellhousing might be preferable if you intend, for example, to adapt a Chevy Turbo 350 using a Wilcap 8BA adapter or use a Tremec 5-speed. Speedway carries a Tremec kit; however, it does not include the necessary bellhousing. The good news is that a reasonable choice of aftermarket adaptors is available.
Early blocks, such as this 239-ci 1946–1948 59A 24-stud with integral bellhousing, work for some hot rod applications. They have a larger bore than the 1938–1942 models, and various transmission adapters make for good swapping material.
The 1949–1953 blocks, without the integral bellhousing, accommodate a wider variety of transmissions (for example, the Chevy Turbo 350), for which Wilcap has an adapter kit.
If you plan to purchase just a block, some pre-purchase research is necessary, because not all flathead Fords are created equal. Lots of minor changes occurred between 1932 and 1953, and the nuances can be confusing.
Pre-1938 21-stud engines have three head bolts in a line down from the central water neck. However, these engines are becoming old and are less desirable than the post-1938 24-stud engines, if only because more cylinder head options are now available.
This one had me confused until I learned that the aftermarket offered a kit to mount the coil remotely. Speedway still produces a similar coil adapter kit.
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: