People from team integra tell me that the number after the c is basically where its manuefactured from. ( 5 is us, 3 is like europe, 4 is like australia, etc...im not too sure about the numbers im just picking them off the top of my head) anways...the only one that doesnt have a number is the JDM one it just says B18C...

Basically the same motor as i understand it...