406 Steam Hole question.

[C20-67_N_MO]

*** MODS **** I know this should be in the Engine forum but more folks look here!. Thanks.

Okay I got a friend of mine that we both bought this 406 SBC engine this past weekend. Well we were curious about the pistons if they were dome topped and what not.

After we found that out we saw that there was not steam hole drilled in the nice port 461 heads. And since he want to run Aluminum heads instead of the iron ones he decided to drill them by himself.

The deal is they do not go into a water jacket.

So my question is are they called steam holes for releasing steam only or are they suppose to have some kind of water flow on this 400 SBC engines?

Thanks for any help you can give.