This 4pc Set of NGK Iridium IX Spark Plugs fits your 03-05 Indmar 8.1L MPI Vortec with 8 Cyl GM Big Block engine and is perfect for a performance upgrade or tune-up. NGK Spark Plugs

4pcs 03-05 Indmar 8.1L MPI Vortec NGK Iridium IX Spark Plugs 8 Cyl GM Big vp


Item Specifics

This listing is for 4 Spark Plugs. Be sure to purchase the correct number of plugs for your vehicle.

NGK Iridium IX Spark Plugs are the choice of consumers, automotive enthusiasts, street racers and professional race teams around the world. Produced using advanced materials and cutting-edge technology, NGK spark plugs help maximize engine power and operating performance ride after ride.

  • Extreme performance upgrade over OEM, V-Power, G-Power, and Standard grade plugs.
  • Exceptional durability, with a 40,000 to 50,000 mile service life.
  • Plugs feature a fine-wire Iridium center electrode and Nickel-alloy ground electrodes for maximum engine horsepower and torque.
  • Designed for fuel-injected and turbocharged engines.
  • Precision laser-welded electrode construction.
  • Trivalent Metal Plating provides superior anti-corrosion and anti-seizing properties.
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Returns and Exchanges


Many of the parts we sell at Sixity only work with specific vehicles. Please double-check the accuracy of your order before purchasing. Check that the reference number, size, and placement are correct. Feel free to contact us with any product or fitment questions.

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About Sixity


Sixity, Inc. launched in 2006 and is based outside of Sacramento, California. We have a dedicated team of product engineers, technicians, and sales staff to bring you the best possible products for your ATV, motorcycle, snowmobile, car, or truck.

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