Denso Iridium Power Plugs Two Step Colder IKH24

Part #: DEN 5346-IKH24-GRP



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Denso Iridium Power Plug Two Step Colder IKH24 Instock
QTY (4)


Brand: Denso
Heat Range: 24
Plug Gap: .032
Stock Number: 5346
Mfgr. Warranty: 1 year or 12,000 miles
Return Policy:

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Subaru Impreza
WRX STI 2004, 2005, 2006, 2007WRX STI Limited 2007WRX STI Hatchback 2008, 2009, 2010, 2011, 2012, 2013, 2014WRX STI Special Edition Hatchback 2010WRX STI Limited Sedan 2011, 2012, 2013, 2014WRX STI Limited Hatchback 2011, 2012, 2013, 2014WRX STI Sedan 2011, 2012, 2013, 2014WRX TR 2006, 2007WRX Limited 2006, 2007WRX 2006, 2007WRX Sedan 2008, 2009, 2010, 2011, 2012, 2013, 2014WRX Hatchback 2008, 2009, 2010, 2011, 2012, 2013, 2014WRX Premium Sedan 2010, 2011, 2012, 2013, 2014WRX Premium Hatchback 2010, 2011, 2012, 2013, 2014WRX Limited Sedan 2010, 2011, 2012, 2013, 2014WRX Limited Hatchback 2010, 2011, 2012, 2013, 20142.5 GT Sedan 2009, 20102.5 GT Hatchback 2009, 2010
Subaru Legacy
GT Limited 2005, 2007, 2008, 2009GT 2005, 2006GT spec.B 2006, 2007, 2008, 2009
Subaru Forester
XT 2004, 2005XT Premium 2005XT Limited 2006, 2007, 2008Sports 2.5 XT 2008
Subaru WRX STI
Base 2015, 2016Limited 2015, 2016Launch Edition 2015

DENSOs Iridium Long Life plug is fast becoming the standard for todays high-tech engines. The properties of DENSOs patented Iridium alloy have broken through the spark plug technology barrier. Employing a revolutionary new 360 laser welding process, DENSO has created a spark plug unlike anything on the market today. Designed for durability under the most extreme conditions, DENSOs patented Iridium alloy is six times harder and eight times stronger than conventional platinum and can handle temperatures in excess of 4,000F.
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  • AnswerQ: QUICK QUESTION  KGABBS 3 months ago

    Is there a downfall to going ahead and running 2 steps colder in a 2011 WRX STI Hatch, even if I'm not currently very far from stock vehicle, but with plans on making big power in the near future?

    • A: These plugs will likely be too cold for your current set up. You are supposed to drop a step colder for every 75-100 HP gained. I would stick with stock heat range plugs on your current set up.

      Josh P. 3 months ago

  • AnswerQ: E85  s20525xxx 7 months ago

    Hi, there, I'm running one step colder atm with E85, and car is misfiring sometimes. I have already bought Okada coil pack, should I also run these plugs to eliminate misfiring? Car has 180hp over stock atm. Maybe also reduce the gap?

    • A: These might be a good solution for you. I would check with a tuner/shop to find out if they think this will fix the issue.

      Trevor C. 7 months ago

  • AnswerQ: compatibility  chipperoo55 1 year ago

    i have a 2010 legacy 2.5l Turbo and have been using NGK SILFR6B 8, mods include turbo back exhaust, HKS power flow. I have dyno tuned the car. 1. can i change plugs to these after the tune or has to be before 2. are these compatible with my car. Thanks,

    • A: Stock heat range is likely the best option for your vehicle and those modifications, these two steps colder plugs are going to be for much higher power vehicles. If you do switch heat ranges doing so before a tune is recommended.

      Nick S. 1 year ago

  • AnswerQ: Proper gap  Ruger 1 year ago

    I know these plugs come pre-gapped but is there a specific gap setting for Sti's? I would think there is but I want to be sure before I install them

    • A: These plugs are pregapped at .032 which is similar to OEM but your tuner may have different recommendations for gap.

      Nick S. 1 year ago

  • AnswerQ: SPARK PLUG APPLICATION  ICEBO1 2 years ago

    The car is 550 WHP SUBARU 2004 STI using a BENSON sleeved COSWORTH (SB 8005) 2.5 liter shortblock with PORTED WRX 2 lilter HEAD (was dyno using standard spark). As this is a hybrid using 2.5 liter shortblock and a 2 liter head, What is the best spark plug should i use on the car?

    • A: We recommend going to a two step colder plug.

      Kyle A. 2 years ago