The accepted heads part numbers are 18350 Canfield and 1399/165 AFR both with 167cc intake port and 67cc exhaust port. The SS horsepower is 230 with intake/Exhaust sizes of 1783/1457 inches.
I would call the manufacturers direct to see if the heads come with the proper valve size and then measure them after I got the heads (see Indy disqualification of Evan Smith).
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