how to port swirl ports

Don't mean to hijack, my aplogies to the OP, just saw this thread and it's in line with what I have going at the moment as well, so I thought I'd ask a few questions about these heads, with Duster's blessing I hope.

Looking at the severely pinched intake ports I assumed they were some lousy flowing heads with no quench in the chambers, and had written them off. My application isn't high RPM performance oriented,{4800 max} but rather a TBI motor with strong low/mid torque for my Ramcharger.

One more question and I'll leave the OP to his thread. Are these heads prone to crack between the seats like early Magnums? Do I need to be wary of overheating these heads wheeling here in the desert? I haven't had any problems with the current 360 getting hot, but the more I'm aware of the shorter the walk home will be.