ZRP +0,35mm Intake Valves Black Nitride for Fiat Abarth Grande Punto 1.4L T-Jet

Fiat 1.4L Abarth / T-Jet / Grande Punto – ZRP +0.35 Black Nitride Intake Valves (Set of 8)

ZRP +0.35 mm Black Nitride Intake Valves are designed for the Fiat 1.4L 16v Abarth / T-Jet engine platform, including Grande Punto and Bravo models. The slightly oversized (+0.35 mm) design improves intake flow efficiency while maintaining excellent compatibility with performance cylinder head builds.

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

Unlike localized chrome coatings, the entire valve — including both stem and head — receives the black nitrided treatment. This ensures uniform protection against wear and valve seat recession, extending service life in both naturally aspirated and turbocharged engines.

Each valve is precision forged, CNC-machined, polished, and tip hardened to meet strict dimensional tolerances. This guarantees accurate seating, stable operation at high RPM, and reliable sealing performance under increased thermal and mechanical loads.

The +0.35 mm oversize configuration makes these valves ideal for mildly ported cylinder heads and performance-oriented engine builds.

Technical Features

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

• Oversize: +0.35 mm

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

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

• Full black nitriding of stem and valve head

• Tight tolerances for concentricity, straightness, and sealing surface finish

Advantages

• Improved intake airflow efficiency

• Reduced stem-to-guide friction

• Enhanced durability and fatigue resistance

• Longer service life compared to untreated stainless-steel valves

• Suitable for high-performance street and motorsport applications

Additional Information

• Set Quantity: 8 valves

• Material: Black Nitride

• Valve Size: 27.25 mm / 5.99 mm / 95.20 mm

• Engine Codes: 312A1, 198A

• Application: Fiat 1.4L 16v Abarth / Grande Punto / Bravo