NGK IX Iridium Spark Plug (Set of 4) - 93501

The NGK Iridium IX Spark Plug (Part #93501 / LKAR7BIX-11S) — sold here as a convenient set of 4 — is NGK's performance-focused iridium upgrade designed for today's high-tech, high-output engines. Built specifically for the performance enthusiast, this NGK iridium spark plug delivers extreme ignitability, exceptional anti-fouling performance, and a consistently stable spark across a wide range of applications including select Acura, Honda, Infiniti, Lexus, Mazda, Nissan, Pontiac, and Scion vehicles. If you've been searching for a direct-fit NGK iridium IX spark plug that improves on the OE plug without requiring custom gapping work on most applications, the 93501 is a well-regarded choice in the NGK lineup.

Key Features & Benefits

• Fine Wire Iridium Center Electrode (0.6mm): The ultra-small 0.6mm iridium tip concentrates the electrical charge for a more focused spark, supporting reliable ignition even in demanding conditions. Iridium's extremely high melting point makes it well-suited for high-performance, high-heat engine environments.
• Extreme Ignitability & Anti-Fouling: NGK specifically highlights this plug's extreme ignitability and exceptional anti-fouling characteristics — meaning it resists carbon buildup that can degrade performance over time, helping maintain smooth idle and throttle response.
• Outstanding Acceleration & Fuel Efficiency: A cleaner, more consistent spark supports more complete combustion, which NGK associates with improved acceleration feel and high fuel efficiency for this series.
• Trivalent Metal Plating: The shell features trivalent metal plating for superior anti-corrosion and anti-seizing properties — a practical benefit that makes future plug removal easier, especially important on aluminum cylinder heads.
• Corrugated Ribs on Insulator: Corrugated ribs on the ceramic insulator prevent flashover, protecting ignition integrity under high-voltage conditions.
• Pure Alumina Silicate Ceramic Insulator: Provides superior mechanical strength and better heat transfer, helping the plug maintain optimal operating temperature.
• Copper Core: A copper core aids in heat removal, supporting consistent thermal performance across varying engine loads.
• Triple Seals: Three seals work together to prevent combustion gas leakage past the plug body.
• Projected Ground Electrode with Taper Cut: The taper-cut nickel ground electrode is designed to improve flame kernel growth and overall ignitability.
• Up to 50,000-Mile Longevity: NGK rates this plug for up to 50,000 miles of service life, making it a cost-effective long-term ignition solution compared to standard copper plugs.
• 5kΩ Resistor Built In: The integrated 5k Ohm resistor suppresses electromagnetic interference (EMI), protecting modern vehicle electronics and sensors.

Specifications

• NGK Part Number: 93501
• NGK Part Name / SKU: LKAR7BIX-11S
• Quantity in Set: 4 plugs
• Shell Thread Diameter: 12mm
• Thread Pitch: 1.25mm
• Seat Type: Gasket (Special Gasket)
• Reach: 26.5mm (1.04")
• Hex Size: 9/16" (14mm)
• Terminal Type: Solid
• Pre-Set Gap: 0.043" (1.1mm)
• Center Electrode Material: Iridium — Fine Wire, 0.6mm
• Ground Electrode Material: Nickel — Taper Cut, Projected
• Resistor: Yes — 5k Ohm
• Heat Range: 7
• Longevity Rating: Up to 50,000 miles
• Torque Spec (Cast Iron Head): 10.8–18 lb-ft
• Torque Spec (Aluminum Head): 10.8–14.5 lb-ft
• Warranty: 60 days

Fitment

The NGK 93501 (LKAR7BIX-11S) fits a broad range of vehicles across multiple brands. Confirmed fitment applications from NGK include (verify your specific trim before ordering):

• Honda: 2024–2025 Civic (EX, EX-L, LX, Si, Sport, Sport Touring, Touring, Type R), 2024–2025 HR-V (EX-L, LX, Sport)
• Infiniti: 2024 QX60 (Autograph, Luxe, Pure, Sensory), 2024 QX80 (Luxe, Premium Select, Sensory)
• Mazda: 2024 Mazda 3 (2.5 S, 2.5 Turbo variants, Carbon Edition, Preferred, Premium, Select Sport), CX-30 (2.5 S, 2.5 Turbo variants), CX-5 (2.5 S, 2.5 Turbo variants, Carbon Edition, Signature), CX-50 (2.5 S, 2.5 Turbo), CX-90 (PHEV, Turbo, Turbo S)
• Nissan: 2024 Armada (Midnight Edition, Platinum, SL, SV), Frontier (PRO-4X, PRO-X, S, SL, SV), Murano (Platinum, SL, SV), Pathfinder (Platinum, Rock Creek, S, SL, and additional trims)
• Also fits select: Acura, Lexus, Pontiac, and Scion applications — always verify your exact year, model, engine, and trim using a fitment checker or by contacting our team.

Important: Always confirm fitment against your specific vehicle's year, make, model, engine displacement, and trim before installing. Thread diameter (12mm), reach (26.5mm), and heat range (7) are key parameters to cross-reference with your OE plug.

What's in the Box

• 4 × NGK LKAR7BIX-11S Iridium IX Spark Plugs (Part #93501)

Why Buy from ThreePiece.us

At ThreePiece.us, we make it straightforward to get the right NGK iridium spark plugs for your vehicle. Every order ships free, no matter the order size — so you're not paying extra to get four plugs to your door. Need to spread out the cost of a full tune-up or ignition service? We offer financing through Affirm, letting you buy now and pay over time. Our team is available to help verify fitment if you have any doubts about whether the NGK 93501 is the correct plug for your engine — just reach out before you order. We carry NGK's full range, so if you need a different heat range, thread size, or plug style for your application, we can point you in the right direction.

Frequently Asked Questions

Q: What is the pre-gapped gap on the NGK 93501, and do I need to re-gap it?
A: The NGK LKAR7BIX-11S comes pre-gapped at 0.043" (1.1mm) from the factory. NGK generally advises against re-gapping fine-wire iridium plugs, as adjusting the gap can damage the delicate 0.6mm iridium center electrode tip. Confirm your vehicle's specified gap matches this setting before installing — for most listed fitments, the factory gap is correct.

Q: What size socket do I need to install these plugs?
A: The NGK 93501 uses a 9/16" (14mm) hex, so you'll need a 9/16" spark plug socket for installation. NGK specifies a torque of 10.8–18 lb-ft for cast iron cylinder heads and 10.8–14.5 lb-ft for aluminum cylinder heads — always torque to spec rather than guessing by feel.

Q: How long will the NGK Iridium IX 93501 last?
A: NGK rates the Iridium IX series for up to 50,000 miles of service life. Actual longevity can vary based on engine condition, fuel quality, and driving habits, but iridium plugs are significantly more durable than standard copper plugs due to the material's extremely high melting point and resistance to electrode wear.

Q: Is the NGK 93501 the same as the LKAR7BIX-11S?
A: Yes — 93501 is NGK's numeric stock number, and LKAR7BIX-11S is the alphanumeric part designation for the same plug. Both refer to the identical NGK Iridium IX spark plug sold in this listing as a set of 4. You may see either number referenced across different sources; they are interchangeable identifiers for this specific plug.