hey speedaddic,
if your after bang for buck, then turbo engines will be your best bet.Id say along lines of ca18det.Ofcourse check legality of any engine conversion before spending heaps just to find out you can't register the car if thats what ur intentions are.
im hoping to modify an a12 and run it in the future.Id say build a crazy a12 mate.im not sure of driving a methanol a12 though and how it would respond in the street.