That same head design and valve arrangement is shared by all the similar engines, 216, 235, and 261. It's not particularly efficient or modern, dating back to the mid-1930's at least, possibly further. Between the nail-head intake and the shrouded exhaust valve, the design doesn't make a lot of sense, at least to me. Maybe the designers had some specific purpose in mind, but whatever it was isn't immediately apparent.

No, it definitely isn't a "Compound Vortex Combustion Chamber"!

https://medium.com/emmett-on-wheels...olled-combustion-cvcc-works-d28f85d61372

LOL!
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!
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