Rare Dodge Dart GT? Which engine is this?

The "Race Engine" part >>>.

Here is the way they worded it:

"said that it’s a 340, >>> with cylinder heads from a 318 “Race Engine.”

So the short block was a 340 (which would have come factory with the 340 performance cam).

But that the 318 heads came from a "race engine".

Possibly some stock car track 318 heads with bigger valves and a port job, but still with the smaller 318 combustion chambers to help up the compression more.

Would be interesting to know what year the 340 short block is?
I am betting '72-'73. Could easily tell what year it is by the front crankshaft vibration dampener. Internal or External balanced crankshaft.