Product Summary

Universal Fit, Gasket Spark Plug Seat Style

    Key Specs

    MFG. Part #AR3910X

    Need To Know

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    Autolite AR3910X Details

    Autolite Racing spark plugs feature a X gap ground electrode, anti-corrosive nickel plating, and large ground electrode for better heat transfer. Heat range needed with Standard tip or Power tip Coldest. 

    • 14 mm plug
    • .75" reach
    • 5/8" hex
    • Gasket seat
    • Non-resistor
    • X gap ground style
    • Vendor Number: AR3910X

    Please use the Vendor Number to reference the PDF chart links listed.

    Please use the Vendor Number to reference the PDF chart links listed.



    CARB Warning

    For race/ off road use only

    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. 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.

    Autolite AR3910X Specifications

    MFG. Part #AR3910X
    Spark Plug Seat StyleGasket
    Seat TaperGasket
    Spark Plug Reach0.75"
    Thread Pitch14mm
    Insulator TypeNon-projected
    Core MaterialCopper
    Tip MaterialChromium Nickel Alloy
    Wrench Size5/8"
    Sold in QuantityEach
    GTIN Code009100032218