That's what I call dogshit, in more ways than one. They should have, noticed it/known it, used/switched to pass car valves...or sold you on 11/32 1.94/1.60 +.050 or +.100.
2 diff lengths of push rods and differing geometry between the int/exh.
As they say though.."it'll run" "he'll never know the diff"..and so on..
You went through the trouble to port the heads...unless you ported then to offset the power loss 'aka like to tread water'.. return them.
Fix it now.
