B18C crank and rods into B16A engine and you have 1.8 litre engine displacement.

Can this be done with no problem or not? Or is it neccesary to buy B18 block aswell?

 

i know they sell a who kit Here which will give you 1.54 ration

you could get a tech43 kit from steve but i heard mixed results about it.

I did a search and someone is thinking about doing the following.
ls rods 137mm and b16 crank 77.4mm which would have a 1.77:1 ratio, the ls rods are 2.6mm longer then the b16. you may want to look into that or do some research on.