Anyone had the head off and seen if the F23 block is open or closed deck. If you don't know Open deck means there is a space between the Cylinder walls and the block for coolant, closed deck the cylinder walls are braced up against the block, like if you added a Block gaurd. Just checking to see how strong the block is! I know the F20B accord SiR motor has Iron sleeves that are solid deck and can handle some mean boost, I am hoping that the f23 at least is closed deck.