Porsche 997 Carrera S gets quality Borla Performance Cat-Back The Borla love affair with the Porsche goes back many decades. Alex Borlabegan his racing career driving endurance Porsches in Europe. The Borla Cat-Back systems for the 997 model of the revered 911 Carrera S series is a perfect blend of exceptional performance and that exclusive Borla tone. PN140234 Cat-Back features a full dual system which, thanks to the lightweight premium, high-quality T-304 stainless steel construction, is actually more than 10% lighter than the factory single muffler system. This 2-?? system is tuned for the non-turbo Boxster engine, boasting an impressive 325cfm greater air flow while generating solid double-digit horsepower numbers and torque gain numbers in the mid-twenties. The 140234 system features four 3.5? Intercooled, mirror polished T-304 stainless steel tips. The Borla PN140233 Cat-Back system is similar, but features the 88mm round polished T-304 stainless steel angle cut tips (two per side). Borla the original pioneers of high quality, T-304 stainless steel (superior to 409 or aluminized steel) free-flow exhaust utilizes patented award and race winning technology to deliver quality, sound, performance gains and enhanced fuel economy -- all with an easy bolt-on installation. And backed by an unsurpassed written million-mile warranty.