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NGK Iridium IX Performance Spark Plugs - Heat Range 6 (03-04 Cobra; 07-14 GT500)

Market Price $79.99 You Save 13% ($10.00)

$69.99 (set of 8)

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  • Item 525003
  • MPN# 3689

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Features & Details

  • Perfect for Stock Boost
  • Iridium Tip for a Constant Stable Spark
  • Improves Fuel Economy and Lower Emissions
  • Heat Range: 6
  • NGK Part# TR6IX; NGK Stock# 3689
  • 14mm Thread Pattern
  • Spark Plug Reach 0.690"
  • Fits 2003-2004 SVT Cobra and 2007-2014 Shelby GT500
  • Sold as a Set of 8
High Performance. Keeping your Mustangs high performance engine running smoothly and efficiently is important, so routinely replace your old weak plugs with a new set of NGK Iridium IX Performance Spark Plugs for constant reliable spark power. The Iridium IX plugs from NGK will provide improved throttle response, fuel efficiency, lower emissions, and will reduce fouling.

Superior Materials. NGK Iridium IX Performance Spark Plugs feature a copper core electrode for its superior conductivity and an iridium tip (which is 6X harder than platinum) for it's extremely high melting point, perfect for keeping your Mustangs high-performance engine running at it's peak. And as an added bonus the Iridium IX plug features Trivalent Metal Plating for it's superior anti-corrosion and anti-seizing properties.

Application. This set of eight (8) NGK Iridium IX Performance "Heat Range 6" Spark Plugs are specifically designed for the 2003-2004 SVT Cobra and 2007-2014 Shelby GT500 Mustangs that are running stock boost.

Fitment: 2003 2004 2007 2008 2009 2010 2011 2012 2013 2014 Details

What's in the Box
  • (8) Spark Plugs
Installation Info
Will it fit my Mustang?
  • GT500 - 07, 08, 09, 10, 11, 12, 13, 14
  • Cobra - 03, 04

Most Helpful Reviews

5/5
Shelby plugs

these took care of the misfire, detonation problems I was having with the upgraded mufflers and tune. runs much smoother and a bit faster. good call...thanks AM

Helpful (1)

5/5
Solved my problem!!

I installed these plugs on my 10psi supercharged 03 mach 1 and solved my surging issues that were happening at cruising rpms (2k or less), I gapped them to 34 and have had no more issues. Thanks AM!!

Helpful (0)

Overall Rating 5 out of 5 stars
Read All 2 Reviews

Customer Photos

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1 Questions / 1 Answers

Ask a Question

Are these one piece or two like the stock ones?

Groomzee

  • The NGK Iridium IX Performance Spark Plugs are two piece spark plugs.

    KevinD92

    Good Answer (1) (0)

Question Resolved

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Customer Reviews (2) Write a Review

Overall Rating 5.0

out of 5 stars

Installation Time:Afternoon

  • Performance Gain 5 5
  • Fit 5 5



  • 5/5

    Installation Time: Afternoon

    September 12, 2014

    Shelby plugs

    these took care of the misfire, detonation problems I was having with the upgraded mufflers and tune. runs much smoother and a bit faster. good call...thanks AM

    waveblastr

    Year: 2011 Submodel: GT500 Tallahassee, FL, USA

    Helpful (1) (0)

  • 5/5

    October 11, 2016

    Solved my problem!!

    I installed these plugs on my 10psi supercharged 03 mach 1 and solved my surging issues that were happening at cruising rpms (2k or less), I gapped them to 34 and have had no more issues. Thanks AM!!

    Gmantj

    Year: 2003 Submodel: Mach 1

    Helpful (0) (0)

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