NGK PFR7B 4853 Laser Platinum Spark Plug Audi S4 S6 BMW Alpina Subaru WRX STI

Vehicle Fitment

• 1991 Audi 200 Quattro (2.2L I5 Turbo, AWD)
• 1992-1994 Audi S4 (2.2L I5 Turbo, AWD)
• 1994-1995 Audi RS2 (2.2L I5 Turbo, AWD)
• 1995 Audi S6 (2.2L I5 Turbo, AWD)
• 1980-1991 Audi Quattro (2.1L-2.2L I5 10V/20V Turbo, AWD)
• 2003-2008 BMW Alpina B5 (E60, 4.4L V8 Supercharged)
• 2003-2008 BMW Alpina B7 (E65, 4.4L V8 Supercharged)
• 1992-2006 Subaru Impreza WRX / STI (GC/GD/GG, 2.0L EJ20 Turbo, AWD)
• 2000-2006 Subaru Impreza WRX Turbo (GD/GG, 2.0L EJ20 Turbo, AWD)
• 2003-2006 Subaru Legacy GT / Outback XT (2.0L EJ20 Turbo, AWD)
• 1993-2002 Nissan 200SX S14 / S15 (SR20DET, 2.0L Turbo, RWD)

Fitment Notes

• PFR7B is one heat range colder than stock OE; recommended for modified, chipped, or tuned turbocharged applications with 0-75 hp over stock power levels.
• Subaru fitment applies to EJ20 Turbo engines (WRX and STI variants); naturally aspirated Subaru EJ engines use a different plug.
• BMW Alpina fitment is specific to the supercharged N62B44A19 V8; standard N62 non-supercharged applications use a different plug.
• Audi fitment covers both 10V and 20V variants of the 2.1L-2.2L I5 Turbo; confirm engine code before ordering.
• Sold individually (1x plug per unit); cylinder count varies by application (4, 5, or 6 plugs required per vehicle).
• Recommended gap: 0.028" (0.7mm); always verify and adjust gap before installation - do not use plier-type gappers on fine-wire platinum tips.

Features

• Laser-welded fine wire 1.0mm platinum center electrode delivers a precise, stable spark and resists wear from high-boost turbocharged operation.
• Platinum pad on the ground electrode provides slow, even wear in distributorless (DIS/COP) ignition systems for extended service life.
• Heat Range 7 - one step colder than stock - helps prevent pre-ignition and detonation in modified or boosted engine applications.
• Trivalent metal shell plating delivers superior anti-corrosion and anti-seizing protection for clean removal from aluminum and cast iron heads.
• Pure alumina silicate ceramic insulator provides better strength, heat transfer, and resistance to dielectric punch-through under high voltage.
• Triple gasket seal construction prevents combustion gas leakage around the shell for long-term reliability under sustained boost pressure.
• Corrugated insulator ribs prevent electrical flashover under high-RPM, high-boost conditions.
• 98% pure copper core aids heat dissipation and maintains stable electrode temperatures across the full powerband.

Specifications

• NGK Part Number: PFR7B
• NGK Stock Number: 4853
• Plug Type: Laser Platinum (Dual Platinum)
• Thread Diameter: 14mm
• Thread Pitch: 1.25mm
• Seat Type: Gasket (Flat)
• Thread Reach: 19mm (3/4")
• Hex Size: 5/8" (16mm)
• Terminal Type: Solid (Non-Removable Nut)
• Pre-Set Gap: 0.028" (0.7mm)
• Center Electrode Material: Platinum Fine Wire - 1.0mm
• Center Electrode Tip: Projected
• Ground Electrode: Platinum Pad
• Resistor: Yes - 5,000 Ohm
• Manufacturer Heat Range: 7
• Torque Spec (Cast Iron): 18-25.3 lb-ft
• Torque Spec (Aluminum): 18-21.6 lb-ft
• OEM Cross References: BMW 12120035747 / Subaru 22401AA360 / Nissan 22401-53J17

Included Components

• 1x NGK PFR7B Laser Platinum Spark Plug (pre-gapped at 0.028" / 0.7mm)

Product Description

The NGK PFR7B (Stock No. 4853) is a Laser Platinum spark plug engineered for high-performance turbocharged applications across European and Japanese platforms, including the Audi 200 Quattro, S4, RS2, S6, BMW Alpina B5/B7, Subaru Impreza WRX/STI, and Nissan 200SX. Running one heat range colder than stock OE, it is the go-to plug for modified and chipped builds where increased combustion temperatures demand better heat transfer out of the electrode. The laser-welded 1.0mm fine wire platinum center electrode paired with a platinum ground electrode pad delivers slow, even wear and a consistently stable spark across extended service intervals.

The projected fine wire tip improves flame kernel development for more complete combustion, and the dual platinum construction handles the demands of turbo boost pressure without the rapid erosion seen in standard nickel plugs. Installation follows standard torque specs for the application - no crush washer modification required with the gasket seat design. Whether used as an OEM-equivalent replacement or a performance upgrade on a modified turbo engine, the PFR7B is one of the most widely trusted plugs in the European and Japanese performance community.