38 heads

[JSeery]

B&S I was mainly referring to valve clearance, "take this into consideration" might have been poor wording. With stock heads, the change in valve angle can be an issue. But not sure about the aftermarket heads.

 

[rotorwrench]

The later heads from post war would fit the older engines. A lot of the aftermarket stuff has a different chamber design (crow foot) but most would fit the 59A engines. If it fit a 59A then it would fit any of the early 24-stud types. I don't know about Don Orosco's stuff for the late 21 stud engines. That stuff will likely be available from H&H for a price. All the 24 stud aftermarket stuff should be fine unless it was cast before the war and try to fit a 59A. There is likely not a lot of prewar aftermarket stuff floating around anyway.