5150 AutoSport Pro-Xtreme Valve Springs Kit BMW M50 / M52 / S50 / S52 Engines Maximize your engine’s potential with 5150 AutoSport Pro-Xtreme Valve Springs, designed for BMW M50, M52, S50, and S52 engines. Whether you're building for high-revving street performance or all-out racing, these valve springs are built to handle engine speeds of up to 11,000 RPM with confidence. Available in two kit options—one for 6mm valves and one for 7mm valves—you get the flexibility to match your setup for optimal performance and reliability. Designed for Peak RPM Performance Proven in our very own E36 M3 "Bully" build, these valve springs effortlessly spun to 9,500 RPM under heavy load without skipping a beat. Perfect for high-lift cams and aggressive tunes, the 5150 AutoSport Pro-Xtreme Valve Springs deliver flawless valve control, preventing float even at extreme RPMs. Precision-Engineered for High-Performance Builds These springs are carefully designed to handle the demands of track-focused applications, forced induction setups, and naturally aspirated builds tuned for high RPMs. They offer consistent performance, ensuring your engine runs smoothly under extreme conditions, whether you're racing on the track or pushing your limits on the street. Note: Installation requires the expertise of a professional engine builder. Key Features: Available for 6mm and 7mm valves to fit your specific application Capable of supporting engine speeds up to 11,000 RPM Tested and proven to handle 9,500 RPM in our E36 M3 "Bully" build Ideal for use with high-lift camshafts and aggressive tuning Engineered for BMW M50, M52, S50, and S52 engines BMW M50 Applications: 3 Series 1990-1995     E36     320i / 325i / 325is1994-1996     E35/E36     318ti 5 Series 1990-1996     E34     520i / 525i1991-1996     E34 Touring     520i / 525i Z Series 1995     E36/E37     Z3 2.0i / 2.5i BMW M52 Applications: 3 Series 1994-1999     E36     320i / 323i / 323is / 328i / 328is1997-2000     E35/E36     318ti / 323ti 5 Series 1996-1998     E39     520i / 523i / 528i 7 Series 1996-1998     E38     728i / 728iL Z Series 1996-1999     E36/E37/E38     Z3 2.0i / 2.2i / 2.8i BMW S50 US Applications: 3 Series 1994-1995     E36     M3 BMW S52 Applications: 3 Series 1996-1999     E36     M3 Z Series 1998-2000     E36/E37/E38     Z3M