318 LA hp and torque question

I almost suggested Magnum manifolds vs headers.
Not a bad idea IMO.
If you can secure a set of the 920 casting heads from a 273, they're about the same specs, never heard of them cracking and nobody wants them (everybody wants 302 heads). Might look in to it.
I know how well the 302's port out. Don't known about other 318/273 heads.