2015 Subaru WRX STI Spark Plugs

Experience the perfect blend of durability and performance with this Iridium TT Spark Plug. Engineered with a 0.4mm Iridium Center Electrode, the world’s smallest diameter, it maximizes firing potential for unmatched ignition efficiency. The 0.7mm Needle Tip Ground Electrode enhances spark energy while minimizing heat quenching, ensuring consistent performance. Built with DENSO’s patented Iridium-Rhodium alloy formula, this spark plug boasts the highest concentration of iridium for superior durability, even under extreme conditions exceeding 4000 Deg F. The 360-degree laser welding process guarantees a robust bond and structural integrity, making it a reliable choice for long-term use. Designed to deliver the durability of an OE-style plug while enhancing power and torque, this spark plug is a high-performance upgrade for your vehicle. With its flat seat type and advanced materials, it ensures optimal compatibility and efficiency, making it a valuable addition to any engine.

Product Features:

• 0.4mm Iridium Center Electrode: World’s Smallest Diameter that maximizes firing potential
• 0.7mm Needle Tip Ground Electrode: Promotes higher spark energy and less heat quenching
• DENSO Patented Optimized Iridium-Rhodium Alloy Formula: Highest concentration of Iridium vs. competitors for greater durability
• DENSO Patented 360 degree laser welding process: Ensuring exceptional quality bond and structural strength with the Iridium Center Electrode
• Durability of an OE style plug combined with Power and Torque of high performance.
• Withstands temperatures greater than 4000 degree Fahrenheit
• Iridium TT

NGK Laser Iridium High Ignitability spark plugs offer the best combination of performance and longevity. Engineered specifically for OE applications, Laser Iridium High Ignitability spark plugs are tested to the highest standards to ensure quality and durability. Iridium tipped center electrode provides durability six times harder than platinum. NGKs high grade pure alumina ceramic and 98 percent pure copper core prevents the spark plug from overheating while providing reliable starts. Laser Iridium High Ignitability spark plugs feature raised platinum pad or platinum fine wire tip on the ground electrode for even wear in distributorless ignition systems and improved spark performance.

Product Features:

• ACTUAL OE or EQUIVALENT HIGH IGNITABILITY DESIGN: SPE tip & iridium alloy center electrode produce the most advanced OE spark plug technology
• IRIDIUM ALLOY CENTER ELECTRODE: Iridium’s density (6x that of platinum) and extremely high melting point is perfect for modern high efficiency engines
• SPE DESIGN: Square platinum electrode shape of the ground electrode provides the best ignitability and service life for high heat engines
• SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
• TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
• RECOMMENDED USAGE: Best for vehicles with OE SPE iridium alloy plugs
• High Grade Pure Alumina Ceramic: Prevents overheating and ensures reliable starts, enhancing overall engine performance.
• Raised Platinum Pad or Platinum Fine Wire Tip: Ensures even wear in distributorless ignition systems, improving spark performance and longevity.
• OE Series Design: Engineered specifically for original equipment applications, tested to the highest standards for quality and durability.

Autolite Copper spark plugs are designed to deliver reliable performance, ensuring quick starts and the power your vehicle demands. Featuring a copper core center electrode, these plugs excel in thermal control and resist fouling, while the high nickel alloy center and ground electrodes provide extended life and durability. The high alumina multi-rib ceramic insulator enhances thermal conductivity and insulation, offering superior strength. With a corrosion-resistant nickel-plated shell, these spark plugs are built to withstand the test of time. Engineered for optimal fuel efficiency, they help you save on gas while delivering smooth acceleration for an improved driving experience. Meeting or exceeding Original Equipment Service (OES) design Standards, Autolite Copper spark plugs are a trusted choice backed by over a century of engineering expertise and the sale of over 11 billion plugs. Designed with a flat seat type and mid-projection standard electrode, these spark plugs are the industry standard for dependable performance.

Product Features:

• The copper core center electrode aids in thermal control and improves resistance to fouling.
• Its specially engineered high nickel alloy center and ground electrode provides extended life.
• The high alumina multi-rib ceramic insulator provides thermal conductivity and superior insulation for increased strength.
• Designed with a nickel-plated shell that is corrosion resistant to provide increased durability for extended periods.
• Good Fuel Economy: Designed to optimize fuel efficiency, these spark plugs help you get the most out of every gallon of gas.
• Smooth Acceleration: Experience seamless and smooth acceleration with Autolite Copper Core spark plugs, enhancing your driving experience.
• OES Design Compliance: These spark plugs are crafted to meet or exceed Original Equipment Service (OES) design requirements, ensuring high-quality performance.
• Industry Standard: Autolite Copper Core spark plugs are recognized as the industry standard, backed by over 100 years of engineering expertise and the sale of over 11 billion plugs.

NGK Ruthenium HX High Ignitability spark plugs are the best in class plug for todays modern vehicles. Patented Ruthenium technology offers the most advance tip technology and delivers the highest performance and life expectancy. Created from advanced OE technology as a high ignitability plug, Ruthenium HX spark plugs come with patented, specialized OEM DFE and PSPE tip designs. NGK Ruthenium HX High Ignitability spark plugs provide a more complete fuel burn resulting in a quicker throttle response, smoother idle and better cold starts. Ruthenium center electrode provides industry leading durability.

Product Features:

• HIGH IGNITABILITY PROJECTED SQUARE PLATINUM ELECTRODE DESIGN: Combines 0.6 millimeter ruthenium center with a unique cut-back PSPE ground electrode
• RUTHENIUM ALLOY CENTER ELECTRODE: NGK’s patented ruthenium technology produces maximum performance, ignitability & durability at high temperatures
• PSPE DESIGN: Projected square platinum electrode shape of the ground electrode provides the best ignitability and service life for high heat engines
• SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
• TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
• RECOMMENDED USAGE: Modern vehicles using OE PSPE type spark plugs or for those seeking an aftermarket plug with the latest OE technology
• High Ignitability Design: Ensures a more complete fuel burn, resulting in quicker throttle response, smoother idle, and better cold starts.
• Specialized OEM Tip Designs: Features patented DFE and PSPE tip designs for optimal performance in modern vehicles.
• Industry-Leading Durability: Ruthenium center electrode provides exceptional durability, making it a reliable choice for long-term use.

The Double Platinum Power Spark Plug is engineered for drivers seeking enhanced performance and durability. Featuring a fine-wire platinum center electrode and a platinum pad ground electrode, this premium spark plug ensures greater wear resistance and sharper spark focus for reliable ignition. Its Heat-Active alloy optimizes electrode temperature under all engine loads, delivering consistent performance and improved ignitability. The V-trimmed ground electrode further enhances spark precision, while the flat seat design ensures a secure fit. Designed as a standard replacement, this spark plug is equipped with a resistor to minimize electrical interference. Built to maintain stable operating temperatures and withstand demanding conditions, it offers long-lasting performance and exceptional value for your vehicle.

Product Features:

• Double Platinum Power – Premium Spark Plug. More Powerful Performance.
• Platinum center and ground electrode for greater wear resistance
• Maintains stable operating temperature under all engine loads
• Fine-wire center electrode for greater ignitability
• V-trimmed ground electrode promotes sharper spark focus
• Heat-Active alloy allows electrodes to reach optimal temperature

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, the Autolite Iridium XP spark plugs feature an iridium-enhanced 0.6mm finewire design and patented platinum sidewire technology to provide better overall durability and a more focused ignition for enhanced ignitability and performance. Features double Iridium-enhanced alloy technology center electrode for improved durability and wear resistance.

Product Features:

• 0.6 mm finewire design improves ignitability
• Patented V-trimmed platinum sidewire technology resists wear
• OE equivalent design is engineered for every engine
• Designed for better overall durability with virtually no gap erosion
• Double Iridium-Enhanced Alloy Technology Center Electrode: Offers improved durability and wear resistance for a longer-lasting spark plug.
• Designed and Engineered in the USA: Reflects over 100 years of Autolite’s engineering experience and expertise.
• Gasket Seat Type: Ensures a secure and proper fit for optimal performance.

Autolite Platinum spark plugs are crafted for superior performance and durability, making them ideal for older engine applications. Featuring a platinum center electrode firing tip, these spark plugs ensure quicker firing, smoother starts, better acceleration, and improved fuel efficiency. The platinum firing tip resists gap erosion, extending service life, while the high alumina ceramic insulator enhances thermal conductivity and insulation for added strength. A multi-rib insulator prevents flash-over, and the nickel-plated shell offers exceptional corrosion resistance for long-lasting durability. Designed with a mid-projection standard center electrode and nickel ground electrode tip, these spark plugs deliver reliable performance under demanding conditions. Engineered in the USA with over a century of expertise and backed by the sale of over 11 billion plugs, Autolite Platinum spark plugs are a trusted choice for drivers seeking enhanced engine efficiency and durability.

Product Features:

• Engineered with a platinum firing tip that prevents gap erosion for longer service life.
• Its high alumina ceramic insulator provides thermal conductivity and superior insulation for increased strength.
• The multi-rib insulator prevents flash-over.
• Designed with a nickel-plated shell that is corrosion resistant to provide increased durability for extended life.
• Engineered in the USA: Backed by over 100 years of engineering expertise and over 11 billion plugs sold.

Double Platinum Spark Plug offers enhanced durability and performance with its platinum-to-platinum design, effectively reducing gap erosion and minimizing misfires for a longer service life. Engineered for distributor-less ignition system (DIS) engines, it outperforms copper and standard platinum plugs. The yttrium-enhanced ground electrode ensures superior heat transfer, maintaining durability under high temperatures and pressure. Its high alumina ceramic insulator optimizes thermal conductivity and dielectric strength, while the multi-rib insulator prevents flash-over for reliable operation. Featuring a mid-projection center electrode and flat seat type, this performance-grade spark plug is built with platinum-tipped electrodes for consistent ignition and lasting reliability. Designed to deliver exceptional value, it is a dependable choice for maintaining peak engine performance.

Product Features:

• Engineered with a platinum-to-platinum design that prevents gap erosion, extending the life of the spark plug.
• The yttrium-Enhanced Ground Electrode delivers superior heat transfer that delivers more durability under high temps and pressure for greater life.
• Its high alumina ceramic insulator provides optimum thermal conductivity and dielectric strength.
• The multi-rib insulator prevents flash-over.
• Designed with a mid-projection center electrode and flat seat type to ensure consistent ignition and reliable performance in demanding conditions.

The Spark Plugs are the product of years of fundamental research in the combustion field. The unique patented electrode configuration of these new The spark plugs increases the amount of combustion pressure created during each power stroke of an engine, which results in a marked increase in power output, fuel economy, and reduced emissions in all gasoline engines. E3.68 is a 14mm, 1.000 reach plug with a gasket seat. It fits a wide variety of late model applications, especially Hemi applications. E3.68 is widely stocked in automotive retail stores. The automotive plugs have three legs securing the Diamond FIRE electrode to the shell. This allows for excellent heat transfer, and helps to create more turbulence in the cylinder. The patented Diamond FIRE side wire is proven to increase power, reduce fuel consumption and improve hydrocarbon emissions in long-term use.

Product Features:

• E3’s Diamond Fire edge to edge ground electrode provides maximum performance with increased efficiency and a faster more complete burn
• Smoother Acceleration & Idle – The faster flame initiated by the spark plug results in a more complete burn of the ingested fuel charge. More pressure is created against the piston more fuel is put to work
• Energy – Power output improved up to 6% on average in the typical operating ranges. Results will vary.
• Efficiency – The “diamond shaped” side wire electrode projects the combustion spark in a way that more quickly ignites the air/fuel mixture, thereby creating a significantly faster and larger flame kernel. The result is that more fuel is put to work durin
• E3’s patented Diamond Fire Technology provides a cleaner burning combustion, which translates into fuel savings and reduced engine carbon deposits
• The Spark Plugs are pre-gapped at the factory and cannot be adjusted.
• Wide Compatibility: E3.68 spark plugs are 14mm with a 1.000 reach and a gasket seat, fitting a wide variety of late model applications, especially Hemi engines.
• Enhanced Heat Transfer: The three legs securing the Diamond FIRE electrode to the shell ensure excellent heat transfer and create more turbulence in the cylinder for better combustion.
• Widely Available: E3.68 spark plugs are widely stocked in automotive retail stores, making them easily accessible for consumers.

The Iridium Power Spark Plug features the world’s smallest Iridium Center Electrode at just 0.4mm, delivering unmatched spark precision for maximum combustion and performance. Engineered with a patented 360-degree laser welding assembly process, it ensures durability and reliability even under extreme conditions. The U-groove and taper-cut ground electrode design optimizes flame propagation, while its ability to withstand temperatures exceeding 4000 Deg F guarantees long-lasting performance. Burnished nickel plating enhances resistance to high temperatures and corrosion, making it ideal for a wide range of applications, including classic and collector cars. This spark plug requires 5,000 fewer volts to fire compared to conventional plugs, ensuring superior performance, enhanced horsepower, and improved fuel efficiency. Whether you’re seeking faster starts, fewer misfires under heavy loads, or better overall engine efficiency, this Iridium Power Spark Plug is designed to deliver exceptional results.

Product Features:

• World’s smallest Iridium Center Electrode (0.4mm) for improved spark for maximum combustion
• Patented 360-degree laser welding assembly process
• U-groove and taper cut ground electrode to maximize flame propagation.
• Withstands temperatures greater than 4000 degree Fahrenheit
• Burnished nickel plating for high temperature endurance and superior corrosion resistance
• Wide range of part numbers for thousands of applications, including classic and collector cars
• Iridium Power
• Superior Performance: This spark plug requires 5,000 less volts to fire compared to conventional spark plugs, providing maximum performance even under extreme conditions.
• Enhanced Horsepower and Efficiency: Experience more horsepower, faster and easier starts, fewer misfires under heavy loads, and better fuel efficiency with the DENSO Iridium Power spark plug.

The Platinum TT Spark Plug features a cutting-edge twin-tip design with a platinum center electrode, ensuring superior conductivity for efficient and consistent ignition. Its titanium-enhanced ground strap adds exceptional durability, making it a reliable choice for long-lasting performance. Engineered to optimize flame propagation, this spark plug promotes more complete combustion, improving engine efficiency and power output. The flat seat type ensures a secure fit, while the advanced materials enhance ignition reliability, making it ideal for automotive enthusiasts seeking enhanced performance and durability.

Product Features:

• Platinum Twin-Tip Design: The Denso Platinum TT Spark Plug features a twin-tip design with a high-quality platinum center electrode, ensuring excellent conductivity and enhanced ignition performance.
• Titanium-Enhanced Ground Strap: Equipped with a titanium-enhanced ground strap, this spark plug offers superior durability and longevity, making it a reliable choice for your vehicle’s ignition system.
• Superior Conductivity: The platinum center electrode tip provides excellent conductivity, ensuring efficient and consistent ignition for improved engine performance.
• Enhanced Ignition System: Designed to enhance your vehicle’s ignition system, the Denso Platinum TT Spark Plug delivers superior performance and reliability, making it an ideal choice for automotive enthusiasts.
• Optimized Flame Propagation: Engineered to promote more complete combustion, this spark plug enhances engine efficiency and power output for a smoother and more powerful driving experience.

Autolite Iridium Ultra Laser Fine wire Spark Plugs are one of our brand’s most technologically advanced products. These spark plugs provide superior durability, more focused ignition with better overall ignitability for optimum performance. Autolite Spark Plugs are the best alternative to OE spark plugs, offering OE fit form and function supporting all foreign and domestic makes and models at a value price. Autolite provides the automotive aftermarket and original equipment manufacturers with the highest quality ignition products and is the leading supplier of spark plugs in the world.

Product Features:

• Autolite Iridium Ultra is an engineered OE replacement iridium spark plug.
• A laser-welded 0.5mm pure iridium finewire center electrode provides optimal fuel efficiency, acceleration and focused ignitability.
• Nickel-plated shell to resist corrosion.
• High-alumina ceramic insulator for increased strength.
• Laser welded 0.5mm Iridium finewire center electrode.
• Proprietary platinum sidewire technology.

The U-Groove Spark Plug features a patented U-groove ground electrode design that enhances ignitability, allowing for leaner fuel mixtures and improved engine efficiency. Built with a nickel center electrode tip and a flat seat type, this spark plug ensures reliable performance and compatibility with a wide range of vehicles, including classic and collector cars. Precision machine-rolled threads minimize the risk of seizing or cross-threading in aluminum heads, making installation smooth and secure. Designed to last twice as long as conventional plugs, it delivers over 30,000 miles of dependable operation. Each plug is 100% pre-fired to guarantee consistent performance, making it an excellent choice for maintaining OE-level performance in your engine.

Product Features:

• Patented U-groove ground electrode design fires leaner mixtures than conventional plugs
• Precision machine-rolled threads reduce seizing and cross-threading in delicate aluminum heads
• Wide range of part numbers for thousands of applications, including classic and collector cars
• Lasts twice as long as most conventional plugs
• 100 percent pre-fired to assure reliable operation
• U-Groove Conventional

NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. NGK Iridium IX plugs offer extreme ignitability and exceptional anti-fouling. Tapered cut ground electrode provides improved starting, idling and throttle response. The Iridium fine wire center electrode’s durability is six times harder than platinum. Iridium alloy’s extremely high melting point is perfect for today’s engines. For even greater performance consider upgrading to an NGK Ruthenium HX plug.

Product Features:

• SINGLE IRIDIUM TIP: Fine wire 0.6 millimeter iridium tip center electrode ensures high durability and a consistently stable spark
• IRIDIUM ALLOY CENTER ELECTRODE: Iridium’s density (6x that of platinum) and extremely high melting point is perfect for modern high efficiency engines
• TAPERED CUT GROUND ELECTRODE: Reduced quenching design produces outstanding ignitability, improved acceleration, fuel efficiency and durability
• SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
• TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
• RECOMMENDED USAGE: Modified or high performance applications, or as an upgrade to OE nickel alloy spark plugs
• Outstanding Acceleration and High Fuel Efficiency: NGK Iridium IX spark plugs are engineered to deliver superior acceleration and enhanced fuel efficiency, making them ideal for performance enthusiasts.
• Extreme Ignitability and Anti-Fouling: These spark plugs offer exceptional ignitability and anti-fouling properties, ensuring reliable performance and longevity.

Engineered to meet the highest OE standards for performance, durability, and emissions, this Iridium Long-Life Spark Plug is a top-tier choice for your vehicle. Featuring DENSO’s patented Iridium Alloy with a 90% Iridium fine wire center electrode, it delivers exceptional spark performance and longevity. The platinum ground electrode ensures extended life, while the 360-degree laser welding process guarantees a robust bond and structural integrity. Designed to endure extreme temperatures exceeding 4,000 Deg F, this spark plug is perfect for high-performance ignition systems and special fuel setups. With a lifespan of over 100,000 miles, it lasts up to three times longer than conventional plugs, offering unmatched reliability and value. The flat seat type ensures a secure fit, making it a durable and efficient solution for your ignition system needs.

Product Features:

• Latest OE technology with DENSO’s patented Iridium Alloy (90 percent Ir) and fine wire center electrode
• Platinum ground electrode for extended life
• DENSO Patented 360 degree laser welding process: Ensuring exceptional quality bond and structural strength with the Iridium Center Electrode
• Sustained spark performance over 100,000 miles
• Lasts up to three times as long as conventional plugs
• Endures extreme temperatures greater than 4,000 degrees F associated with high-performance ignition and special fuel systems
• Iridium Long Life

NGK G-Power Platinum spark plugs are the best single platinum spark plugs at an economical price. G-Power plugs feature a fine wire platinum center electrode and a trapezoidal cut ground electrode that offers increased durability, improved fuel efficiency, lower emissions, faster starts and quicker acceleration over conventional nickel spark plugs. An excellent upgrade for vehicles which used nickel alloy spark plugs originally. For better performance consider upgrading to a NGK Iridium IX plug. For even greater performance consider upgrading to a NGK RUTHENIUM HX plug.

Product Features:

• SINGLE PLATINUM TIP: Fine wire 0.6 millimeter platinum tip center electrode ensures improved durability and a consistently stable spark
• PLATINUM ALLOY: G-Power platinum provides exceptional value with increased performance and longer service intervals than factory nickel plugs
• TRAPEZOIDAL CUT GROUND ELECTRODE: Reduces quenching design produces improved ignitability and performance
• SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
• COLD-ROLLED THREADS: Prevents cross-threading and damage to cylinder heads
• RECOMMENDED USAGE: Lower cost alternative to double precious metal spark plugs or as an upgrade to OE nickel alloy spark plugs