NGK
Laser Platinum Spark Plug

NGK 5851 Spark Plug

Brand NGK 5851
Center Electrode Core Material Copper
Center Electrode Tip Material Platinum
Electrical Terminal Type Non-Removable Nut
Ground Configuration Standard
Ground Electrode Core Material Nickel
Ground Electrode Quantity 1
Ground Electrode Tip Design Standard
Hex Size 5/8
Insulator Height 50.00
Manufacturer Heat Range 8
Part Number PMR8A
Pre-Gap Size .028
Reach .75
Resistance 5000
Seat Type Flat
Stock Number 5851
Thread Diameter 10.00
Product line Laser Platinum Spark Plug
Fits Aprilia, Ferrari, and Maserati · 10 vehicles

OE supplier heritage. Built by NGK, a long-time original equipment spark plug manufacturer.

Platinum tip. Helps deliver consistent ignition performance and durability.

Copper core. Promotes efficient heat transfer for stable operation.

Cross-references MAHLE 5851, 168325 and PG2PHP for the same application. See all 4.

$23.59Free shipping
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NGK Laser Platinum Spark Plug for OE Fitment

The NGK Laser Platinum Spark Plug 5851 is built for precise ignition performance in select Ferrari and Maserati applications. It combines a platinum center electrode with a nickel ground electrode and OE-style dimensions to support consistent spark delivery and stable engine operation.

Key Features

  • Laser Platinum design with a platinum center electrode tip
  • Copper center electrode core for efficient conductivity
  • Nickel ground electrode core with standard ground configuration
  • 0.028 pre-gap size and 5000 resistance
  • Flat seat, 10.00 mm thread diameter, 0.75 reach, and 5/8 hex size
  • Non-removable nut terminal for OE-style connection

Product Details

NGK Laser Platinum Spark Plug 5851 is engineered to match original equipment requirements for select high-performance engines. The PMR8A design uses a platinum tip to support durable spark performance, while the standard ground electrode layout and OE-style dimensions help maintain proper combustion characteristics. This spark plug is listed for 2000-2004 Ferrari 360, 2003-2004 Maserati Coupe, and 2002-2004 Maserati Spyder applications, making it a direct-fit choice for owners searching for a Ferrari 360 spark plug or Maserati Coupe spark plug replacement.

NGK’s long OE supply history and manufacturing focus on domestic and import ignition components support the consistency expected from a premium replacement plug. The 5851 part number is also referenced in interchange listings for MAHLE 5851 and cross-references 168325 and PG2PHP for the same application.

Common Issues This Part Can Address

  • Misfires caused by worn or fouled spark plugs
  • Hard starting from weakened ignition output
  • Rough idle related to inconsistent spark delivery
  • Reduced throttle response from degraded plug performance
  • Maintenance replacement for OE-spec ignition service intervals

Installation Notes and Tips

Verify the specified gap before installation and confirm the flat seat, 10.00 mm thread diameter, 0.75 reach, and 5/8 hex size match the engine specification. Use the correct torque procedure for the cylinder head material and inspect ignition coils, boots, and wires during service to avoid repeat misfire concerns. For fitment verification, match the vehicle application exactly: Fits 2000-2004 Ferrari 360, N/A; Fits 2003-2004 Maserati Coupe, N/A; Fits 2002-2004 Maserati Spyder, N/A.

Quality Assurance

NGK manufactures ignition components to OE standards and supports this spark plug with its established reputation as an original equipment supplier for a wide range of automotive applications.

This part fits 10 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersPositionNotes
2004Ferrari3603.6LV8N/A0.028 inch gap suitable for OEM application.; Laser Platinum Spark Plug
2004MaseratiCoupe4.2LV8N/A0.032" Gap; OE Equivalent Design; Laser Platinum Spark Plug
2004MaseratiSpyder4.2LV8N/A0.032" Gap; OE Equivalent Design; Laser Platinum Spark Plug
2003Ferrari3603.6LV8N/A0.028 inch gap suitable for OEM application.; Laser Platinum Spark Plug
2003MaseratiCoupe4.2LV8N/A0.032" Gap; OE Equivalent Design; Laser Platinum Spark Plug
2003MaseratiSpyder4.2LV8N/A0.032" Gap; OE Equivalent Design; Laser Platinum Spark Plug
2002Ferrari3603.6LV8N/A0.028 inch gap suitable for OEM application.; Laser Platinum Spark Plug
2002MaseratiSpyder4.2LV8N/A0.032" Gap; OE Equivalent Design; Laser Platinum Spark Plug
2001Ferrari3603.6LV8N/A0.028 inch gap suitable for OEM application.; Laser Platinum Spark Plug
2000Ferrari3603.6LV8N/A0.028 inch gap suitable for OEM application.; Laser Platinum Spark Plug
Directly replaces or cross-references 4 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
MAHLE — 5851168325PG2PHPRA4PHP