hey i got a b18a1 block and b20z pistons and a p75 (b20) head just wonding if i bored the block to 84mm (i think thats the b20 piston size) and put the p75 head on it would work with valve clearance and be all hunky dory? any insite grateful 
no one?
basically you’re gonna bore out ur b18a1… and drop in larger pistons/rings…then deck the block/head if its got warpage…then slap it all together… just so u can have a BASICALLY stock b20z? why not just find a stock b20 block u can put the pistons into?
and if u do the work urself on boring out the block, u’d have to make sure the clearances were in spec, like for the piston-to-wall clearance, piston/rod, ring gap clearance, bearing clearances for the rod-to-crank, etc.
then if u did all that u might as well replace all the bearings cuz they’re pretty worn. then the oil pump.
ur valve clearance shouldn’t be an issue as long as u compensate for any loss in deck height with the proper size head gasket.
all this work when u can just pick up a b20 block (bare or not) and just drop in ur b20z pistons.
need an water pump also