Supertech MEVI-1019-8 – +1 mm Oversize Inconel Exhaust Valve Set (Mitsubishi 4B11 T / Evo X)
Supertech MEVI-1019-8 delivers eight +1 mm oversize exhaust valves crafted from heat-proof Inconel® for the 2.0 L 4B11T engine found in the Mitsubishi Lancer Evolution X and Ralliart. Designed for high-temperature, high-boost use, they outlast OE steel valves while freeing up exhaust flow for greater power potential.
Key Features
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+1 mm head diameter (30 mm) – larger curtain area improves gas evacuation and supports higher horsepower at elevated RPM.
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Inconel 751 nickel-base alloy – retains strength and resists oxidation beyond 900 °C, essential for turbocharged applications.
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One-piece forged construction – eliminates weak weld seams, boosting fatigue resistance during prolonged high boost.
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Single-groove keeper – compatible with most Supertech and OEM retainer/spring packages for straightforward installation.
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Black-nitride stem coating – harder surface (~52 HRC) reduces guide wear and stem friction, enhancing valvetrain stability.
Technical Specifications
| Parameter | Value |
|---|---|
| Valve type | Exhaust |
| Head diameter | 30.00 mm (+1 mm) |
| Stem diameter | 5.46 mm |
| Overall length | 105.9 mm |
| Tip length | 3.10 mm |
| Material | Inconel 751 |
| Surface treatment | Black Nitride |
| Keeper style | Single groove |
| Pieces per set | 8 |
Vehicle Compatibility
| Brand | Model | Generation / Chassis | Engine |
|---|---|---|---|
| Mitsubishi | Lancer Evolution | Evo X | 4B11T |
| Mitsubishi | Ralliart | Evo X | 4B11T |
SUPERTECH
Supertech Mitsubishi 4B11 EVO X Inconel Exhaust Valve - +1mm Oversize - Set of 8
Tags: Engine\By Car Make\Mitsubishi\4B11,
| Brand | Model | Generation | Engine |
|---|---|---|---|
| Mitsubishi | Lancer Evolution | Evo X | 4B11T |
| Mitsubishi | Ralliart | Evo X | 4B11T |