For a b20 application you will need atleast 84mm pistons. Unfortunently there is no real good solution for a OEM style 84mm piston for a CRV/VTEC build.

So baisically you need forged rods & pistons such as Wiesco pistons / Eagle rods to achieve a good static C/R for a CRV/VTEC build.

I have heard of some companies such as topline that are considering making a replica Jdm ITR or JDM p30 piston in 84mm. I personally wouldnt waste my time researching into a non forged piston & rod setup to save a few bucks.