Autolite AR3910X 14mm Racing Spark Plug, 5/8 Inch hex, 3/4 Reach
Universal Fit, Gasket Spark Plug Seat Style, Gasket Seat Taper, 0.75" Spark Plug Reach
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
- X gap ground style
- Vendor Number: AR3910X
Please use the Vendor Number to reference the PDF chart links listed.
Heat Range Chart (PDF)
Racing Plug Tech Note (PDF)
Understanding Heat Range (PDF)
- Get FREE shipping when your order includes this item and exceeds $99! Ground shipping only in the contiguous US.
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