Are you sure it is the standard A12 cylinder head? Not maybe a Big port GX or A15 cylinder head fitted?
If it is true, congratulations. I just wonder, how long will the engine last with that power figure and boost level. Now that is a thought. Before you put in the A14, won't you play a bit with the car and see how long the A12 last? Take to a drag race event or something. Give it some hammering and test for us the reliability factor.