You will need 2 per car. Building your own turbo manifold on your Audi 30V V6 2.7T Engine? These exhaust manifold flanges will make the process go much smoother. Engineered for an exact fit and manufactured right here in United States. These flanges are precisely laser cut from 1/2" thick steel, Integrated Engineering manifold flanges are a must for the DIY manifold builder! Features: 1/2" thick steel 1.6" ID ports Made in U.S.A.