1932 to 1933 Main Bolts through to Lalter Valley
1932 to 1934 No Cam Bearings
1932 to 1934 36 Tooth Cam Gear
1932 to 1936 Babbit Mains ('36 had both types)
1932 to 1936 2.00" Main Journals
1932 to 1936 Water Pumps in Heads
1932 to 1937 Timing Gear Pressed On
1932 to 1938 Rod Housing Bores 2.200"
1932 to 1938 21 Stud Heads
1932 to 1938 1.937 Rod Bearing Width (Flanged)
1932 to 1940 Core Plugs in Oil Pan Rails
1932 to 1942 2.00 Rod Journals
1932 to 1945 3 1/16" Bore
1932 to 1945 No Rear Seal
1932 to 1945 Irregular Water Holes
1932 to 1945 One Oil Hole Per Rod Throw
1932 to 1948 2 Piece Valve Guides
1932 to 1948 Mushroom Valves
1932 to 1948 Integral Bellhousing
1935 to 1948 Main Studs
1935 to 1948 Oil Filler/Breather Tube
1935 to 1948 44 Tooth Cam Gear
1935 to 1948 3 Cam Bearings
1936 - 1937 Thick Wall Main Bearings
1937 to 1938 2.400" Main Bearings
1937 to 1948 Water Outlets in Center of Heads
1937 to 1948 Water Pumps in the Block
1938 to 1948 Timing Gear Bolted On
1939 to 1946 1.750" Rod Bearing Width (No Flange)
1939 to 1942 2.00" Rod Journals (1.750" Wide)
1938 to 1948 24 Head Studs (Mid year change '38)
1939 to 1948 2.500" Main Journals
1941 to 1942 Raised Intake Mount (Not Proven)
1942 to 1948 Rod Housing Bores 2.360"
1942 to 1948 2.139" Rod Journals (1.750" Wide)
1942 to 1953 2.139" Rod Journals
1942 - 1945 WAR, No General Production
1946 to 1948 Triangle and 2 Round Water Holes
1946 to 1948 3 3/16" Bore
1946 to 1948 Rear Main Caps with Drain Tubes / No Seals
1946 to 1948 "59" Casting
1949 to 1953 "Shorty Oil Pump
1949 to 1953 2 Oil Holes Per Rod Throw
1949 to 1953 Individual Rod Bearings
1949 to 1953 2 Oil Holes in Rod Throws
1949 to 1953 Distributor Moved to Top Right
1949 to 1953 Bolt on Bellhousing
1949 to 1953 One Piece Valve Guides
1949 to 1953 Modern Style Valves and Keepers
1950 to 1953 New Helical Gear Design Oil Pump