This unit is a complete bolt-on that functions perfectly with the stock tune

2-Year Limited Warranty

Step 2: Tighten to 50 ft-lbs

Compact Yet Powerful

Viton Valve Stem Seals, BMW S58 BMWSH1-CV-S This unit is a completeViton Stem Seals for High Performance BMW S58 Engines Viton Stem Seals are engineered to prevent oil from entering the combustion chamber, ensuring optimal engine performance. Crafted from premium Viton material, these seals offer superior control and durability across the entire RPM range. Their compact design allows for clearance in small inside diameter valve springs. Developed to withstand the extreme conditions of high horsepower and turbocharged