340 mismatched heads?

HotRod20 said
Picked up a set of 1970 340 engine heads from the cars original owner who decided to go with
a 392 Hemi conversion. He still has the block and crank. So while looking at the heads, I noticed one was a O head and the other was a Z head. I measured the intake valves on both heads and both measured with a digital caliper @ 2.02. Looks like the heads were cast a month apart,10069 and 11129. Part numbers were both 915's
Kind of odd dont you think??.. I guess anything goes at the factory back in the day...Lol..

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Could have been what it left the factory with but who knows for sure. Or sometime along the history of the engine, somebody changed a head. I had 2 different heads on my 66 273 but the odd head matched up with the oddball rod bearing with a later date. Something happened along the lone.