on the testing we had done with the 3 inch down pipes that were available back in the day when open downpipes were what was being used. The mistake we made was not recognizing that the issue was the down pipe design rather then the pipe size. When we made the 2.5" split down pipes we assumed this was the best idea based on the tests that were done with open down pipes. We are all always learning, I have been working on just Nissan Z cars since 1982 and I still do not know everything there is to know about them. I can tell you that I will always try to offer what I believe to be the best and I will always strive to push for improvement.
