i want to know more about cummins heads
They are heavy, have lousy casting consistency, have an integrated intake manifold that is garbage, crack too easy, and are out flowed by even the worst vw head. If the cummins bottom end wasn't so redonkulus in stock form, and found in so many applications making parts cheap, there is no way I would touch it.
Supposedly someone is going to release an aftermarket head before to long, with some decent ports too it, but I am not holding my breath.
I can't tell you much about making the stock ones better, or the valve seats or shit like that, but Dave can, and that is why my heads go to him.