Supertech Performance AIVN-1106S Black Nitrided Intake Valve Oversize Single Groove - 1mm

The Supertech Performance AIVN-1106S is a black nitrided stainless steel intake valve designed as a +1.0mm oversize replacement for high-performance and competition engines. Engineered from a single piece of forged EV8 (21-4N) stainless steel alloy, this valve delivers superior strength, heat resistance, and long-term reliability in demanding performance applications.

Key Specifications:

• Head Diameter: 27.90mm (+1.0mm oversize)
• Stem Diameter: 5.96mm
• Length: 105.10mm
• Material: Forged EV8 (21-4N) Stainless Steel
• Finish: Black Nitride Coating
• Groove Type: Single Groove
• Valve Type: Intake
• Required Keepers: KPR-6S/7 (must be used with this valve)

Key Features:

• One-piece forged construction for maximum strength and structural integrity
• Black nitride treatment applied to the entire valve — not just the stem — bonded at a microscopic level so it will not flake or chip even under high-stress conditions
• Microhardness exceeds 800HV minimum, significantly higher than the base stainless steel material
• Smoother surface finish than chrome-coated stems, resulting in reduced friction between the valve stem and guide
• Black nitride reduces power loss at high RPM by minimizing valve-to-guide friction
• Popular choice for European and Japanese performance applications

The black nitride finish offers a key advantage over traditional chrome coatings: it maintains a tough outer layer while preserving ductility in the underlying material. Because the nitrided layer is adhered at a microscopic level, it remains intact even if the valve experiences bending forces from piston contact — a critical safety characteristic in high-revving performance engines.

Supertech valves are sold individually (per valve). Order the exact quantity needed to complete your engine build — for example, if your engine requires 10 intake valves, order a quantity of 10.