NGK SILZKR7B11 Iridium Spark Plug

Premium iridium technology for lasting performance and fuel efficiency.

Product Overview

The NGK SILZKR7B11 Iridium Spark Plug delivers exceptional ignition performance through advanced iridium and platinum electrode technology. Engineered for vehicles requiring M12 x 1.25 thread spark plugs with 1.1mm gap specification, this premium plug offers extended service life and improved engine efficiency. The fine iridium centre electrode paired with a platinum ground electrode ensures consistent spark energy across extended service intervals, making it ideal for modern engines demanding reliable ignition performance in Australian driving conditions.

Key Specifications

• Part number SILZKR7B11 with precise 1.1mm pre-set gap
• M12 x 1.25 thread pitch with 26.5mm reach dimension
• 16mm hex size for standard socket installation
• Resistor-type construction (5kΩ) for electromagnetic interference suppression
• Gasket seat type for reliable compression sealing
• Iridium centre electrode with platinum ground electrode configuration

Features & Benefits

Fine Iridium Centre Electrode – Six times harder than platinum, the laser-welded iridium tip resists erosion even under extreme combustion pressures, maintaining optimal spark performance through extended service intervals and reducing replacement frequency.

Platinum Ground Electrode – The platinum-tipped ground electrode works in tandem with the iridium centre to minimize electrode wear, ensuring stable idle quality and consistent throttle response throughout the plug's service life.

Trivalent Metal Plating – Advanced corrosion-resistant coating prevents seizure in aluminium cylinder heads common in modern engines, enabling easy removal even after years of service in harsh Australian heat.

Corrugated Ribs Design – Engineered insulator ribs increase surface distance to prevent voltage flashover in high-compression engines, maintaining reliable ignition under demanding operating conditions.

Triple Seal Construction – Three-layer sealing system eliminates combustion gas leakage between the insulator and shell, protecting internal components and maintaining consistent performance.

Copper Core Heat Transfer – Solid copper core efficiently conducts heat away from the firing tip, preventing pre-ignition and electrode overheating during extended highway driving or towing applications.

Pure Alumina Silicate Insulator – High-strength ceramic construction withstands thermal shock and mechanical stress while providing superior heat transfer characteristics for optimal operating temperature.

Technical Specs

• Thread size: M12 x 1.25
• Reach: 26.5mm
• Hex size: 16mm
• Electrode gap: 1.1mm (pre-set)
• Resistor type: 5kΩ suppression
• Seat type: Gasket
• Centre electrode: Fine iridium tip
• Ground electrode: Platinum tip
• Insulator material: Pure alumina silicate ceramic
• Shell plating: Trivalent metal anti-seize coating
• Core material: Copper

Compatible With / Goes Well With

This spark plug is application-specific based on thread pitch, reach, and heat range. Compatibility depends on your vehicle's engine specifications—consult your owner's manual or a qualified mechanic to confirm SILZKR7B11 is the correct specification for your vehicle. Common applications include modern petrol engines requiring iridium plugs with M12 x 1.25 thread and 26.5mm reach.

Caution: Using incorrect spark plug specifications can result in poor performance or engine damage. Always verify part compatibility before purchase.

Weight

Not specified

Frequently Asked Questions

How often should I replace iridium spark plugs?

Most iridium plugs last 100,000–160,000 km depending on driving conditions and manufacturer recommendations. Check your service manual for specific intervals.

Can I adjust the 1.1mm gap on this plug?

No. Iridium electrodes are extremely fine and fragile. The gap is pre-set at the factory and should never be adjusted or you risk damaging the electrode.

Do I need special tools to install this spark plug?

You'll need a 16mm spark plug socket, torque wrench, and gap gauge for verification. Follow manufacturer torque specifications to avoid damaging threads or the gasket seat.

Will this plug improve my fuel economy?

Iridium plugs maintain consistent spark energy longer than conventional plugs, which can preserve fuel efficiency over time. Results depend on overall engine condition and maintenance.

Is this plug compatible with LPG or CNG conversions?

Not all spark plugs suit alternative fuels. Consult your LPG/CNG installer or conversion documentation to confirm this heat range and electrode configuration is appropriate for your system.