I found a 1935 ford with a 21 stud headmounted waterpump v8. The heads are cast iron with cast nbr 66 6050B. From what ive read these engines came with aluminum heads. What are these from?
Probably 68, not 66?? I would need 2 hours in my library to totally flog this question but I believe these are genuine Ford replacement heads made after 1936 production run. Early aluminum heads were often trouble, I think partially from metallurgy and design, partly because of exposure to too much water of varying mineral content rather than anti-corrosive anti freeze and also antifreeze of very poorly chosen content. Anyway, early V8 aluminum heads frequently corroded and warped badly...many had to be removed with hammer and chisel. Some engine rebuilder catalogs I have state that aluminum V8 heads were not acceptable on exchanged engines and would be replaced with new iron heads with price deducted from the exchange. I think without catalogs handy that the 68b heads were later replacements for dome piston type aluminum heads. They obviously are not original to your '35, since 68 is a 1936 PN. Pretty sure they are purely replacement heads never used on production '36 Fords.
Like Bruce mentioned, Ford basically did a "recall" of the day and replaced heads that were warped. cracked etc with cast iron heads. I have a 21 stud with 1 aluminum and 1 cast head. I thinks its cool, when I rebuild it hopefully I can run it like that.
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