any benefit to swapping heads?

Does he not have a heavy car and tall gears?
Aj
have you read Racer Browns long article?
specifically on Datsun but universal truths you have to read through and make notes then go back
Racer developed a couple of grinds for our SS Dodge 413>426 wedge suffered through the three speed and non "Super" T 10 BW 4 speed "problems"
He was a legitimate mechanical engineer
Racer Brown Datsun 510 camshafts & valve timing datsport