This is an analog super-sprint manifold with engineering changes / updates from BmwDoctor: engineering improvements - monolithic pipe design and improved compatibility with the standard exhaust system. Objectives: -increase torque + 10-15% -sportive pleasant sound-catalyst removal headers are produced using leading in Industry-leading technology from the best 304C stainless steel AISI with edging of variable thickness from 1.5 to 1.8 mm. 

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