I was reading on some website that the stock b20z pistons don't have enough valve relief to account for a VTEC head. Does this mean that in order to do a b20vtec one would have to rebuild the bottom end? Would stock b16 pistons (pr3 right?) work, or does the b20 have a greater bore. I was thinking of putting my b16 head on a b20 block.....but I'm not sure what this entails. I tried searching and got some bullshit about using words less than 3 letters; which, btw, is REALLY FUCKING ANOYING!!!!