Product Summary

377, 400, 421, 434, C Piston Ring Style

    Key Specs

    MFG. Part #
    BrandSpeedway Motors
    Piston Ring StyleC
    Piston Ring Diameter

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    By using an 80,000 psi low friction, low porosity plasma moly top ring along with purpose build second and oil rings, we have the best rings for the buck on the market. You will make more horsepower over other brands using these rings due to the unique design and ring face finish. 20+ additional horsepower has been seen using these rings. File fit design.

    • Top 1/16"
    • 2nd 1/16"
    • Oil 3/16"


    CARB Warning

    For race/ off road use or for use on pre-1966 vehicles.

    Emissions warning: this part only legal for sale or use in California for racing (competition) vehicles which may never be used, registered, or licensed for use upon a public highway, or if installed in vehicles model-year 1965 or older; motorcycles model-year 1977 or older; or off-highway recreational vehicles (such as off-road motorcycles and all-terrain vehicles) model-year 1996 and older. Any other use renders the vehicle tampered and not legal for use on California public highways (any public street or roadway, public dirt road, public park, or publicly maintained right of way open to the use of the public for vehicular travel). Violations subject to $37,500 penalty per violation per vehicle, revocation of registration, loss of use on California public right of ways, and proof of correction for tampering. There are similar restrictions and penalties under federal law and the laws of all other states with penalties under federal law of up to approximately $45,268 per tampered vehicle and/or engine.


    MFG. Part #
    BrandSpeedway Motors
    Piston Ring StyleC
    Piston Ring Diameter
    Piston Ring DesignConventional
    Top Ring MaterialPlasma Moly Coated Cast Iron
    Top Ring Thickness1/16"
    Second Ring MaterialPlasma Moly Coated Cast Iron
    Second Ring Thickness1/16"
    Oil Ring Thickness3/16"
    Oil Ring TensionStandard Tension
    Sold in QuantitySet