NGK
Laser Iridium Spark Plug

NGK 3508 Spark Plug

Brand NGK 3508
Resistance 5000
Ground Electrode Tip Design Standard
Ground Configuration Standard
Ground Electrode Core Material Nickel
Electrical Terminal Type Non-removable nut
Center Electrode Core Material Copper
Center Electrode Tip Material Iridium
Pre-Gap Size .032
Ground Electrode Quantity 1
Hex Size 5/8
Insulator Height 50.50
Manufacturer Heat Range 5
Seat Type Flat
Reach .75
Thread Diameter 14.00
Part Number Ifr5t-8n
Stock Number 3508
Product line Laser Iridium Spark Plug
Fits Mazda · 2 vehicles

Laser iridium design. Iridium tip helps deliver precise, consistent ignition performance.

Copper core. Promotes efficient heat transfer for stable operation.

OE standards. Built with original equipment quality and durability in mind.

Cross-references AMS Automotive 4701, Anchor 3303 and Anchor 3435 for the same application. See all 9.

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NGK Laser Iridium Spark Plug for Mazda Miata

The NGK Laser Iridium Spark Plug, part number 3508, is built for precise ignition performance in select Mazda Miata applications. It uses an iridium center electrode, nickel ground electrode, and a 0.032 in. pre-gap to support consistent spark delivery and stable combustion.

Compatible with 2004-2005 Mazda Miata, this NGK 3508 spark plug is a direct-fit ignition service part for drivers maintaining OE-style performance and service intervals.

Key Features

  • Laser Iridium spark plug from NGK
  • Part number 3508 / IFR5T-8N
  • Iridium center electrode tip with copper core
  • Nickel ground electrode with standard configuration
  • 0.032 in. pre-gap
  • 14 mm thread diameter, 0.75 in. reach, flat seat
  • 5 k? resistance and non-removable nut terminal
  • Compatible with 2004-2005 Mazda Miata

Product Details

NGK is a long-established OE spark plug supplier with broad coverage across domestic and import vehicles. The Laser Iridium line focuses on OE-style ignition performance using a fine iridium center electrode for dependable spark consistency and a standard ground electrode layout. For Mazda Miata owners, part number 3508 provides the specified 0.032 in. gap and the correct thread, reach, and seat dimensions for the listed application.

This part cross-references Anchor 3508 for the same application.

Common Replacement Reasons

  • Engine misfire or rough idle
  • Hard starting or extended crank time
  • Reduced fuel economy from worn plugs
  • Loss of throttle response under load
  • Maintenance replacement at the OE service interval

Installation Notes

Verify the engine is cool before removal and confirm the plug gap matches the vehicle specification before installation. Use the correct 5/8 in. hex socket and tighten to the manufacturer’s torque specification for the Mazda Miata application. Check coil boots, plug wells, and ignition components during service to help prevent repeat misfire concerns.

Quality Assurance

NGK manufactures spark plugs to OE standards and supplies ignition components for a wide range of automotive applications. Part number 3508 is built to match the listed fitment and specification details for 2004-2005 Mazda Miata service.

This part fits 2 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersPositionNotes
2005MazdaMiata1.8LL4N/AGap 0.032"; Actual OE Manufacturer; 100,000 mi OE Mfr Recommended Service Interval; Laser Iridium Spark Plug
2004MazdaMiata1.8LL4N/AGap 0.032"; Actual OE Manufacturer; 100,000 mi OE Mfr Recommended Service Interval; Laser Iridium Spark Plug
Directly replaces or cross-references 9 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
AMS Automotive — 4701Anchor — 3303Anchor — 3435Anchor — 3508CSF — 4503IK16TTPK16TTSK16PR-F8SK16R-P8