Tomei Oversized Valve Set Mitsubishi EVO VII VIII IX 4G63 03-07

$536.00 Sale:$492.32


Model #163402

In Stock

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Tomei began operations in 1968 as a race car tuner in Japan. Over the last 40 years Japan has emerged as one of the leaders in automotive research, racing, and culture. Tomei products have been utilized in nearly every motor sport imaginable. Tomei's racing heritage means their research and design team have first hand knowledge of the extreme demands racing puts on an engine. Using only the highest quality materials means that Tomei's products can handle the intense strain and heat a purpose built engine will experience whether it be on the street or the track. Tomei's attention to detail is second to none. All of their products are thoroughly researched and engineered to achieve optimal efficiency. Because of even miniscule differences in measurements can cause catastrophic engine failure, all Tomei products fall within strict tolerances. Tomei machines all of their engine components to enhance airflow and ensure proper fitment and seal.

Tuned engines require as much fuel mixture to enter the combustion chamber as possible. For that reason Tomei as selected a larger diameter design to optimize flow rates. Due to the extremely high temperature conditions experienced in the combustion chamber during high power runs the durability of the valves were also addressed to improve resistance to high heat conditions. Tomei oversized valves are manufactured with the highest quality materials available to ensure they will perform in demanding conditions.

1mm oversized valves were designed for increased flow efficiency on both the intake and exhaust side. The stem has a thinner design for maximizing air flow rate within the port with the reduced air flow resistance. This design also means the end product is lighter than the factory pieces.

  • Improved wear rate
  • Improved fatigue rate
  • Improved heat resistance
  • Improved corrosion resistance
  • Better airflow produces more horsepower than factory valves
  • Valve Diameter: Intake 35mm Exhaust 31.5mm
  • Stem Diameter: Intake 6.57mm Exhaust 6.54mm
  • Stem Length: 109.6mm
  • Proposition 65

    /!\ warningWARNING: Cancer and Reproductive Harm

    Vehicle Engine Notes
    Mitsubishi Evolution

    Mr. Seiichi Suzuki initially forged Tomei is a tuning factory for race cars back in 1968. From that day on, Tomei achieved excellent results in various motor sports categories. Tomei was then recognized for its technology, performance and reliability that we had cultivated into our own design products and had a large support base from motor sports end users and tuners.

    With the new market trends and demands, motoring enthusiasts wanted better performance to suit the new modern lifestyle. This trend helped set the stage where originality can play an active part in the motor sports scene and personal motoring lifestyle.

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