ZRP Std Intake Valves Black Nitride for BMW Mini Cooper 1.5L B38 3-Cylinder

BMW / Mini Cooper 1.5L B38 (3-Cylinder) – ZRP Standard Black Nitride Intake Valves

ZRP Standard Black Nitride Intake Valves are engineered for the BMW / Mini 1.5L B38 three-cylinder turbocharged engine. Designed for high-efficiency, high-RPM, and boosted applications, these intake valves provide excellent durability, dimensional stability, and long-term reliability under demanding thermal and mechanical conditions.

Manufactured from one-piece forged high-grade stainless steel (EV8 / 21-4N), each valve undergoes a specialized black nitriding process. This advanced surface hardening treatment diffuses nitrogen into the outer layer of the valve, significantly increasing wear resistance and fatigue strength while reducing friction between the valve stem and guide due to the smoother, hardened surface.

Unlike localized chrome coatings, the entire valve — including both stem and head — receives the black nitrided treatment, ensuring uniform surface protection and extended service life in modern turbocharged engines.

Each valve is precision forged, CNC-machined, polished, and tip hardened to meet strict dimensional tolerances. This guarantees accurate valve seating, stable high-RPM operation, and consistent sealing performance in both naturally aspirated and turbocharged configurations.

Technical Features

• Base Material: High-grade stainless steel (EV8 / 21-4N)

• Surface Hardness: Nitrided layer up to approx. 800 HV

• Manufacturing Process: Precision forged, CNC-machined, polished, and tip hardened

• Treatment Coverage: Full black nitriding of stem and valve head

• Dimensional Accuracy: Tight tolerances for concentricity, straightness, and sealing surface finish

Advantages

• Reduced stem-to-guide friction for lower wear

• Improved stability at high RPM

• Longer service life compared to untreated stainless-steel valves

• Reliable sealing in both naturally aspirated and turbocharged engines

• Suitable for high-performance street, track, and endurance applications

Additional Information

• Valve Size: 30.10 mm / 4.96 mm / 99.50 mm

• Material: Black Nitride

• Engine Codes: B38B12 / B38B15

• Application: BMW i8, 1 Series, 2 Series, 3 Series, X1 / Mini F55, F56, F57, F54, F60