ThankzZ for all the usefull comments guys I was told that B18C5 and B16B head are ported B16A head . . .

If thats the case, Will it be cheaper to get a B16B or B18C5 head compare to getting a B16A head and have it ported by portflow ? ? and which one would produce better airflow/performance and which one will be more durable ? ? ?

ThankzZ :thumbup: