Large valved 273

This head might work as an upgrade. Still iron, but not a 2.02 valve. I'm sure it highly quality and has more potential than the stock pieces.

Speedmaster As-Cast Cylinder Heads PCE281-1773

1.920 valve, 62cc chamber. (stock chambers ran 57cc to 67cc on 273's)


Ultimately, I feel if the 273 is used, the best route would be a factory head port, maybe an oversized exhaust valve, roller cam and a centrifugal supercharger feeding it.

That overcomes the anemic head and the cubic inch deficiencies.

It would easily make 400-500hp. YOu can look up articles where they built 283 gm engine and put the squeeze on them using stock heads.