The case is that the stock exaust pipe size 2.25 is good enough for 6,7,8whp. Meaning zero flow loss/restrictions.So we are looking at same tune comparing the two with a new style 3.5, and a pull vs a run with open downpipes.looking for as much info as possible. Effect on spool time rpm,hp/trq,egt. So any csv would be awesome.....your the man