Im looking to replace my head with another ls head (b18b) and just build it while its off my car...well i was looking on ebay and this person has a b20z head and he says it fill fit directly onto the b18b bottom end?!?! I was just wondering if that was true information and if it is...what are the advantages of the b20z head compared to the b18b head? Thanks alot for you help:thumbup: