How much gains are expected?
My situation either buy a B16A head(get this port and polished), CTR cams, ITR valves and valve springs and change over the other parts in my B18C to B16A head. Or just buy the ITR head complete? Both are around the same price(B16A slightly cheaper). Im thinking if i go the B16A route the better port and polish will achive more gains. Which leads to the question how much will a PP ITR head achive? Help me decide best option
BTW Poormans ITR setup in GSR.

 

The end result if you have either head ported will be the same.
Just make sure you use the ITR intake valves.

 

Cuz they make mad HP, yo!