I've read many threads and done my searches and have decided there is no discussion happening where people compare the exhaust systems available for the street on a performance level. I am looking at a few systems for my car, but I was hoping that I could spawn a robust discussion that would perhaps crowd source enough information that we could put together a sticky post for people to be able to reference in the future. These are the pieces of information I am hoping to capture, but if you think I missed something please add to it (I am by no means an exhaust expert or I wouldn't need to do this): Impact on HP / Torque at various points along the rev range Materials / longevity / construction Weight Other considerations I think are important because this is a street-application specific thread: Availability Price Fit (240z vs 280z, r180 vs r200 diff, other considerations) Muffler dB Me personally, I am looking at the new version of the Fujitsubo Legalis R twin system, Sean's Z-Story single system, Spirit Garage's twin system, and the Trust header mated to something I haven't figured out yet. I know there are tones of other options so it might be crazy to try to capture a comprehensive set of information, and I am selfishly hoping to get real experienced feedback on the ones I mentioned, but figuring out what performs best for a street application is my overarching goal. Maybe the best way to go about it is for people to nominate an option and give reasons matching my topics above and then for debate to ensue... Or you can just post a link to where this has happened already and I couldn't find it.