NGK Laser Iridium Spark Plugs 94201 SILZKGR8B8S - B58 M140i, M240i, 340i , 440i

Iridium Performance Ignition Plugs for BMW B58 powertrains

Looking to refresh the ignition system on your BMW turbo six without compromise? Choose the NGK OE-spec iridium ignition plug set, part number 94201 SILZKGR8B8S. This is the trusted upgrade for B58-powered models including the M140i, M240i, 340i and 440i, delivering crisp combustion, smooth idle and dependable performance on both standard and tuned cars.

Why enthusiasts pick these for the B58

• Ultra-fine iridium centre electrode for rapid ignition and strong spark stability
• Platinum ground pad for excellent longevity under heat and boost
• Corrosion resistant trivalent coating to help prevent seizing in the cylinder head
• Confident cold starts, sharper throttle response and refined running
• Designed to meet stringent OEM standards for reliability and emissions

We run these plugs in our own builds and customer cars, and the feedback is consistently positive. Whether you are carrying out preventative maintenance or supporting a remap, these are a go-to choice for B58 reliability and consistency.

Ideal for

• BMW B58 3.0 petrol turbo owners prioritising dependable ignition performance
• Routine service intervals, misfire troubleshooting and pre-remap refresh
• Fast-road and daily-driven setups seeking OE-grade durability

Technical details

• NGK Part Number: 94201
• NGK Code: SILZKGR8B8S
• Spanner size: 14 mm bi-hex
• Thread diameter: 12 mm
• Thread reach: 26.5 mm
• Firing position: 4.7 mm
• Resistor: 5 kOhm
• Seat type: Copper gasket
• Centre electrode material: Iridium
• Ground electrode: Platinum pad

Compatibility highlights: BMW M140i, M240i, 340i, 440i using the B58 engine.

Sold individually. Please add the quantity required to your basket.

Professional fitting

Want them installed by specialists? Book fitting with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a quote and availability.

Search-friendly terms

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