VW Golf 2.0L WITH 4bolt manifold flange and 1 02 sensor provision. UNIT FEATURES MANDREL BENT TUBING. Mandrel Bending is a type of bend that keeps the radius constant throughout the entire bend, no crushed or wrinkled pipe. Not only does this look better, the flow is kept within OEM parameters; this translates into far superior performance and fuel economy when compared to just about any aftermarket item !