I dnk for sure what diameter metal's pipes were. I do recall that he had an awesome dyno at the Atlanta tune with 355 HP, and 353 TQ. Everyone commented on how sweet his exhaust sounded. As far as the NW exhaust, yes.... it just goes to where your catback would take over, so it would be up to you to finish it off with a dual catback. But after investing in that exhaust, I would not think anyone would not have a dual catback.

Here is the post where XRay was able to do .25 tenths better on back to back runs first with cutouts closed and second with cutouts open. https://www.crossfireforum.org/forum...ght-track.html He said that he did better than his previous runs to installing the exhaust even with the cutouts closed, ergo the 3-4 tenths estimate. I aslo seem to recall NW posting a 3-4 tenths increase in one of the cars they installed the exhaust on.

At any rate, I am not trying to debate or argue with you about any of this. You stated that you may have the first true dual, and I just pointed out that there are several members that already have a true dual. That is all. Good luck with your project, and I look forward to seeing your dyno results.