Bswanny

Curious if someone could help clarify? I bought the motordyne catback exhaust and art pipes. When installing the art pipes, I don't know what to do about the third bold on the headers to art pipe flange. The diameter of the one threaded hole of the flamge is too small and has a coarse pitch thread. All 10 bolts supplied with the art pipes do not fit. Do I need to drill the one threaded hole per flamge to fit the supplied bolt through? The instructions do not discuss this. I have a 2014 370Z if the year matters. Thank you