I have a jdm b20 (the higher compression model) and recently picked up a pr3 head. My question is will there be a clearance problem? I heard from a close friend that I have to notch the pistons in order for there to be clearance for the valves. I am just dont believe this.

 

You won't have clearance problems with stock parts. It's just a B20Z with a B16A head. Just don't plan on using anything bigger than Type-R cams and if you do use ITR/CTR cams, don't use adjustable cam gears and you shouldn't have contact either.

This answered constantly. Within the last week for sure...
https://honda-tech.com/search.php

 

thanks for the info. Much appreciated