Wha? You mean this
six page PDF?
http://sickbikeparts.com/Manuals/Tuned Pipe Installation Instructions.pdf
I've never in my life seen more comprehensive & detailed instructions pertaining to the relatively simple process of installing & tuning an expansion chamber... I've really no idea what more they could have said lol After all - taco managed to sum it up well in one sentence
Final performance alterations depend so greatly on personal preference, environmental conditions (altitude & terrain type), specific engine type, condition, modification & owner usage that it's impossible to give a specific "just cut here" measurement for maximum "performance"... If they coulda I'm sure they woulda
Additionally, as with most mods - you'll need to compromise one thing for another, you can't simultaneously tune for both top
and low end powerband with just header length.