Valvetronic Design Porsche Boxster/Cayman 981 Valved Sport Exhaust Systemhttps: youtu. be 9vqHkUVVUIk The 981 Cayman and Boxster is a dream platform. Perfectly balanced, but lacking sound from the factory. That is where we come in! Welcome to our catback for the 981 platform. Measuring 2. 5 inches from the headers back, this system takes the already decent sound 981 Porsches into the stratosphere. When operating in the valves open mode, exhaust gasses flow uninterrupted through to our X pipe and out our beautiful 3. 5 inch