[Robk]

I don't think that folding the heart draw is such a simple problem. I think that you have the implied odds to see the turn. You are getting immediate odds of 3-1 on the call. If your opponent will bet again if the flush draw hits on the turn then you figure to win three more big bets, or $24, don't you, giving you implied odds to make the call??
Flush card hits 9/47 for a profit of 24 + 12 = 36
Flush card misses 38/47 for a profit of -4
EV = 36*(9/47) + -4*(38/47) = 6.9 - 3.2 = 3.7 > 0
If your opponent may check when the flush card turns then it's not so clear. But if he's this timid he'll probably check the turn if you raise the flop. Then,
Flush card hits turn, you'll make 16 + 16 = 32. P=9/47=.19
Flush card misses turn, hits river you'll make 16 + 8 = 24
P = (38/47)*(9/46)= .16
Flush card misses both you'll make -8. P= (38*37/47*46)= .65
EV = 32*(.19) + 24*(.16)+ -8*.65 = 6 + 3.84 - 5.2 = 4.64 > 0
Obviously I made a bunch of simplifying assumptions (this second ev should be much lower mainly because he'll sometimes 3-bet and lead, and sometimes the 4th heart will hit the board) but I think it's still a +ev play.
Someone please set me straight if I'm wrong.