The 913 head casting was used on 1954-56 235 full pressure oiler engines. It has a slightly lower compression ratio than the 848 head(56-63) but it can be milled .090" to equal the 848 compression. Recess the intake valves back into the head the same distance to preserve the "quench trench" that keeps the valves from burning if you choose to mill that head. Either head will be a bolt-on fit to pressure oiler 235s or 261 engines.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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