A flathead history

 

Notes on heads

  • 8BA Commonly found on passenger cars after 1948.
  • The 1948 trucks where first released with 59AB blocks in a rush to get them to market.
  • In 1952 the compression ratio was increased from 6.8 to 7.2 to 1 with EAB heads that had a smaller combustion chamber than the 8BA heads and gained 10HP
Year CID Bore Bore Stroke Comp. HP@RPM Torque@RPM Model
1932 221 3.0625 3.75 5.5:1 65@4500   18
1933 221 3.0625 3.75 6.33:1 75@3800   40
1934 221 3.0625 3.75 6.33:1 85@3800   40A
1935 221 3.0625 3.75 6.33:1 85@3800   38
1936 221 3.0625 3.75 6.33:1 85@3800   68
1937 221 3.0625 3.75 6.2:1 85@3800   78
1937 221 3.0625 3.75 7.5:1 94@3800   78
1937 136 2.6 3.2   60@   74
1938 221 3.0625 3.75 6.12:1 85@3800   81A
1938 136 2.6 3.2   60@ 94lb-ft@ 82A
1939 239.4 3.1875 3.75 6.3:1 95@3600   99A
1940 239 3.1875 3.75 6.3:1 95@3600   09A
1940 221 3.0625 3.75 6.12:18 5@3800   01A
1940 136 2.6 3.2   60@ 94 lb-ft@ 022A
1941 239.4 3.1875 3.75 6.3:1 95@3600   19A
1941 221 3.0625 3.75 6.12:1 85@38600 155 lb-ft@ 11A
1942 239.4 3.1875 3.75 6.4:1 100@3800   29A
1942 221 3.0625 3.75 6.2:1 90@3800 155 lb-ft@ 21AA
1946 239.4 3.1875 3.75 6.8:1 100@36800   69A Ford
1946 239.4 3.1875 3.75 6.8:1 100@36800   59A Mercury
1947 239.4 3.1875 3.75 6.8:1 100@3600   79A Ford
1947 239.4 3.1875 3.75 6.8:1 100@3600   79A Mercury
1948 336.7 3.5 4.38 6.8:1 145@ 225 lb-ft@  
1948 239.4 3.1875 3.75 6.8:1 100@3600   89A Ford
1948 239.4 3.1875 3.75 6.8:1 100@3600   59A Mercury
1949 336.7 3.5 4.38   152@ 265 lb-ft  
1949 336.7 3.5 4.38   145@ 225 lb-ft@  
1949 255.4 3.5 4 6.8:1 112@38600   CM
1949 239.4 3.1875 3.75 6.8:1 100@3600   98BA
1950 336.7 3.5 4.38   152@ 265 lb-ft  
1950 336.7 3.5 4.38   145@ 225 lb-ft@  
1950 255.4 3.5 4 6.8:1 112@38600   CM
1950 239.4 3.1875 3.75 6.8:1 100@3600   8BA
1951 336.7 3.5 4.38   152@ 265 lb-ft  
1951 336.7 3.5 4.38   145@ 225 lb-ft@  
1951 255.4 3.5 4 6.8:1 112@38600   CM
1951 239.4 3.1875 3.75 6.8:1 100@3600   98BA
1952 336.7 3.5 4.38   145@ 225 lb-ft  
1952 255.4 3.1875 4 6.8:1 125@ 225 lb-ft@ CM
1952 239.4 3.1875 3.75 6.8:1 110@3800   8BA
1952 239.4 3.1875 3.75 6.8:1 106@3600    
1953 336.7 3.5 4.38   145@ 225 lb-ft  
1953 255.4 3.1875 4 6.8:1 125@225 lb-ft@   CM
1953 239.4 3.1875 4.38 6.8:1 110@3600   8BA
Back to Comments, questions & somewhat helpful information