The photo might make porting look easy, but its not.
The photo should show you how little room for error there is, how easy it is
to take a little to much off here or there and ruin a head. And this does not
address what work will really help and what work will hurt. Extremely small variations make the difference between improvement and making things much worse.
To complicate things there are 8 different ports on each head. No two on the same head are exactly the same. And do to core shifts in casting each head is little different. If you don't recognize this, what works on one head will put you right into the water jacket on another.

And assuming that you don't wreck the head, how do you know that the work you have done will help? Can you flow each port on a flow bench? Put the engine on a dyno to measure the HP improvement. Or just take a wild shot in the dark? And how many heads are you willing to ruin to get one that is right?

John
V-Performance.com