Its been a little while.......

this thread says 70-72 cc
Got some Heads, Which ones are best? - Mopar Forums
Those are the correct vintage heads for a 75-80 360 81-84 318 4bbl and 75-84 truck
they may have smog holes so plug them if not using AIR
came with 1.88 x 1.6 valves installing 2.02 valves has been done before- I hope they opened up the bowls and blended- viton seals so a premium job
basically all large port heads are the same
should have hard ex seats
from stan weiss site 202 intake valve stock heads
================================================100===200====300===400===500
Chrysler 915J Iron HPMM 156/73 2.02/1.60 N/A ---------------------------66/63 --123/110 170/135 206/145 220/148
hrysler 974 Cleaned and milled IQ52 11/32 SS Iron N/A 2.02/1.60 Pipe N/A 65/50- 132/103 184/131 207/143 210/146
Chrysler 974 Cleaned and milled IQ52 Iron N/A 1.88/1.60Pipe N/A---== ----- 58/50 115/92 173/132 202/143 208/145 3/8 stems 1.88 intakes
note how 2.02 helps low lift on unported heads
I frequently use 30 degree seatsfor the same reason
I take the 202 valves and cut the new 30 degree face then I have to reduce the dia slightly because the edge gets too thin then cut the seat out where the current top cut is and then narrow the 45 and so on= really helps the "curtain area" for .500 lift builds good velocity too
does motor have dished pistons?