HKS SUPER FIRE RACING MR45XLZ - Black Ops Auto Works
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HKS SUPER FIRE RACING MR45XLZ

HKS
HKS50003-MR45XLZ
4957266720509
Spark Plugs
3 Units In Stock - Ships Next Business Day
$ 330.00
FREE Ground Shipping!
$ 330.00

SKU: 50003-MR45XLZ | UPC: 4957266720509

HKS SUPER FIRE RACING MR45XLZ Spark Plugs for 2005-2021 Subaru STI Forester XT Legacy GT Outback XT

HKS SUPER FIRE RACING MR45XLZ spark plugs feature iridium construction for turbocharged Subaru EJ25 engines. These plugs fit 2005-2021 Subaru WRX STI Forester XT Legacy GT and Outback XT models. Stronger spark improves combustion for more horsepower torque and throttle response under boost.

Key Features

  • 0.8mm Pure Iridium Center Electrode: Delivers stable spark in high rev high boost conditions for consistent power output
  • 0.8mm Platinum Ground Electrode: Resists erosion and maintains gap for long service life in racing use
  • Projected Insulator Design: Accelerates flame growth to reduce misfires and increase efficiency
  • Heat Range 45: Controls temperature in turbo applications to avoid preignition or fouling
  • M12 x 35mm Thread Reach: Exact match for Subaru EJ cylinder heads with 16mm hex size

Product Notes

  • Sold individually as direct OEM replacement
  • Pre-gapped to 0.8mm verify gap before installation
  • Small lightweight package for fast shipping

Installation Notes

  • Professional installation recommended.
  • Torque to 25 Nm or 18 ft-lbs using 16mm thin wall socket
  • Apply anti-seize compound to threads compatible with OEM coils

This Part Fits

Year Make Model Submodel
2005-2009 Subaru Legacy GT
2005-2009 Subaru Outback XT
2009-2013 Subaru Forester XT
2008-2014 Subaru Impreza WRX STI
2015-2021 Subaru WRX STI -

Why Choose HKS?

  • Leader in JDM tuning since 1973 with motorsport heritage
  • Engineered tested for boosted Subaru applications
  • Made in Japan with precision tolerances

Frequently Asked Questions

  • Q: Does MR45XLZ fit 2015-2021 Subaru WRX STI?
    A: Yes direct replacement for EJ257 turbo engines in 2015-2021 WRX STI models
  • Q: What materials are used in electrodes?
    A: 0.8mm pure iridium center electrode paired with 0.8mm platinum ground electrode for durability
  • Q: What is the service interval?
    A: Up to 40000 miles in street use replace sooner in track or high boost setups

Shipping & Handling

  • Method: UPS Ground or USPS Priority
  • Availability: In stock - ships same or next business day
  • Packaging: Original HKS box dimensions 4in x 3in x 2in
  • Weight: 0.15 lbs

Request For Information

Have questions about HKS SUPER FIRE RACING MR45XLZ? Fill out the form below and we'll get back to you by the next business day.
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