ok you are totally off base. the b16 head is the worst flowing vtec head avalible in stock condition:

here is how it works out
PR3(ITR) > P72 > PR3(B16/B17)

for modified heads which are ported the flow and power characteristics go like this:

P72>PR3(all)

the p72 GSR/SIR-G head will outpower most other heads due to it's smaller chambers, with or without the better flow of the PR3 ITR head. so with or without modification i'd have to say the P72 head is the best head.

now as for the JDM/USDM pistons problem: you can buy brand new JDM pistons for cheap off of h-motors. they will increase your power by leaps and bounds if you are looking for an all motor LS-VTEC.

http://www.hmotorsonline.com/shop/sc...age&item=10016