I think the gsr motor is the best platform to start with especially if you plan to boost later on. and about your original question.. there are a lot of forms of the b18c. jdm ones range from b18c and b18c spec r (pre 98 type r) and b18c spec r(98-01)

usdm are b18c1 (gsr motor) and b18c5 (type r).

I have also heard of a b18c4 from japan, mentioned by mr. spoon himself h: , but I'm not sure what it is from and I'm thinking it is just stamped b18c as well.. probably a good engine