Sold my 428 so got a 351 head question

Bought a 351C and took off the valve cove to see the 9H14 date code...Trying to find out what kind of heads they are. Hope 4V. How can you tell? Also somebody told me once they used to put a 2 or 4 on the front corner of the head. Don't see anything though? Help:whacked:

4V heads are a bit too big for the street unless you plan on running high rpm, like 3500 to 8000 rpm.... The 2V heads will flow plenty for anything but an all out racing c motor......