Supertech Performance Miata Exhaust Valve


Supertech uses over 20 years of manufacturing experience to design and produce their Valves.  Intensive testing and working closely with engine builders provides continuous improvements and provides the market with the best possible product for every application.  High flow rate, durability, and quality are all of great concern.

Supertech understands that each motor is unique in its requirement and demands.  There fore Supertech offers valves in a range of materials to suit any motor.

* Stainless - Made as a one piece forged valve for higher strength and reliability.  Supertech uses mostly EV8 (21-4N) for Intake and Exhaust Valves, however, there are other alloys that are used with different heat treatments to manufacture Valves for specific applications.

To address the issue of high heat, Supertech uses two different types of coatings:

Chrome Coating - Widely used in performance valves

Black Nitride - This is a hardening treatment that provides a smooth surface then chromed valves and produces less friction between stem and guide.

* Inconel 751 - Nickel Base Alloy - Nickel base alloy is used for exhaust valves that reach very high temperatures, such as those in turbo or supercharged applications.

Supertech Valves are sold *Per Valve*. For Example, when order for a Model that requires 16 Valves, order ‘Quantity: 16’


Standard Valve

  • Head Diameter: 28.00mm (STD)
  • Length: 102.60mm (+0.6)
  • Material: Black Nitrated
  • Stem Diameter: 5.94mm.97mm

    +1 Valve

    • Head Diameter: 29.00mm (+1.0)
    • Length: 102.60mm (+0.6)
    • Material: Black Nitrated
    • Stem Diameter: 5.94mm