Akrapovic Evolution Race Line (Titanium) for Porsche 911 GT3/RS (991)Evolution Race Line (Titanium) for Porsche 911 GT3 RS (991) This system is built for the track and gives the Porsche GT3 the extra performance to match. Beautifully made from hi grade titanium and with a coating, the Evolution Race Line is as striking to look at as it is use. From the handcrafted titanium headers with 100 cpsi sports catalytic convertors and titanium flangescast in Akrapovis own foundryright through to the superbly finished round