I did speak to Mark about their head as it is a LOT of money and he said that it is good but it is built to their ideal spec (which I assume is for naturally aspirated engines up to 2.7l) and Mark said that whilst it flows well he would still be modding it to his spec so we have left it that he would port my head until such times as he says yay or nay once he has the engine apart. I would not personally run to the expense of the ally head.

Adding up the cost of Ally block, pistons, arrow crank rods (all for 2.2 or 2.3), head work, cam, labour, mapping and all the other little bits it does get quite scary.