Check out this site pictures:
http://www.honda-tech.com/zerothread?id=1199677

About the SMSP header picture. Is that header consider 4-2-1 or 4-1? Cause the design is 4-2-1 but usually the cylinder 1&4 become 1 and the other is cylinder 2&3 become 1. But in this picture is cylinder 1&2 and the other is 3&4. Can anyone explain? And what is the advantage by using very long pipe for the header? Thanks.