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Up to 66% Off Tire Clearance
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  • Part #: 4055|
  • SKU: 9216659

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    • Fine tipped Iridium center electrode ensures high durability and a consistently stable spark
    • Iridium alloy has an extremely high melting point, perfect for today's high-performance engines
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NGK Iridium IX Spark Plug

NGK Iridium IX spark plugs provide the best ignitablity in a single precious metal spark plug. Iridium IX plugs are best suited for high performance and modified engines which may require a colder heat range. Refer to NGK catalog for more information on selecting the correct Iridium IX spark plug
  • Fine tipped Iridium center electrode ensures high durability and a consistently stable spark
  • Iridium alloy has an extremely high melting point, perfect for today's high-performance engines
  • Trivalent metal plating has superior anti-corrosion and anti-seizing properties
  • Taper-cut ground electrode is designed to open up more area for flame expansion reducing the quenching effect
When you require the best, count on The World Leader in spark plug technology NGK Spark Plugs. We offer the highest quality products for virtually every vehicle application. Count on NGK Spark Plugs to deliver the finest quality products and customer service.


Rated 4.6 out of 5 by 11 reviewers.
Rated 5 out of 5 by One of the BEST PLUGS out there !! These spark plugs woke up my Toyota Rav4. It runs smoother and engine has better throttle responce. I used just a little, i mean just a little antiseize on threads. ALWAYS START THE THREADS BY HAND AND NEVER USE A RATCHET TO START TO THREAD THEM IN TO AVOID CROSSTHREADING. ALWAYS INSTALL ON A COLD ENGINE OR ELSE THREADS IN HEAD CAN GET RUINED. Make sure when tightening these plugs that you crush the washer. You will feel the washer get crushed as you tighten these and then you will know when it is fully crushed. If you are not using a torque wrench, DO NOT GORILLA TIGHTEN the plugs or you risk breaking the plugs. I highly recommend these plugs!! These should be good for 100 thousand miles. September 8, 2016
Rated 3 out of 5 by Good product This product gave my 2006 dodge truck a little bit more power at take off, but really using a lot of fuel. The reviews I read, was the that spark plug saves some fuel consumption. But for my case, I don't why, it now uses a lot of fuel. August 12, 2016
Rated 5 out of 5 by High Quality Product I have used them in my vehicles and other equipment, lawnmowers, power washer, portable air compressor and others. NGK spark plugs have never failed on me as have other spark plugs. Honda recommended changing plugs at 60,000 miles in my 06 Pilot. I inspected and put them back in and ran them to 105,000. I pulled them and they look the same as the 60,000 mile inspection. I did replace them with reluctance. July 3, 2015
Rated 5 out of 5 by NGK IRIDIUM SPARK PLUG This product is one of the best on the market today. The price was very reasonable. April 19, 2015
Rated 5 out of 5 by works great,fast shipping. best price its a spark plug that works what else is there to say December 26, 2014
Rated 5 out of 5 by Really good This plugs are my two ix that i bought, they give me quality and power God bless you! December 23, 2014
Rated 5 out of 5 by Love my lift supports Easy to install March 2, 2014
Rated 4 out of 5 by GOOD PLUGS These NGK spark plugs are factory recommended for my Hyundai Accent. I haven't noticed any difference in mileage (in fact, mileage has slightly decreased, but that's probably because computer hasn't adjusted to the new spark plugs yet). I took the old NGK Iridium plugs out of my car at 68,000 miles and they still looked pretty good. Car peppier and smoother with new spark plugs of course. With such an expensive part like an engine, I stick to factory-recommended plugs. February 17, 2014
  • 2016-10-27 T10:45:46.699-05:00
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