Akrapovic Slip-On Line (Titanium) 991 RSAkrapovics Slip On Line represents the first step in the exhaust system tuning process and the muffler can easily be installed onto the Porsche GT3 RSs original system. Built from hi grade titanium and finished with two eye catching double round tailpipes, this entry system makes the GT3 RS more powerful and lighter, and gives the car that unique Akrapovic sound. Technical Data: Unit Stock Akrapovic Max gain kW 345. 7 8450 rpm 348. 6 8400 rpm + 4. 5