NGK 91874 Spark Plug

Reliable Ignition Performance for BMW and Rolls-Royce Vehicles

The NGK Laser Iridium High Ignitability Spark Plug 91874 is engineered to deliver consistent ignition and efficient combustion for select BMW and Rolls-Royce models. Designed with advanced materials and precise specifications, this spark plug supports optimal engine performance and fuel efficiency.

• Iridium center electrode tip for enhanced durability and ignition
• Square platinum ground electrode tip designed for high ignitability
• Standard ground configuration with a single ground electrode
• Non-removable nut electrical terminal type for secure connection
• Pre-gap size of 0.030 inches for precise spark gap
• Flat seat type with 12.00 mm thread diameter and 25.20 mm reach
• Resistor type spark plug with 5000 ohm resistance to reduce electrical noise
• Hex size 14 bi-hex for proper installation torque
• Manufacturer heat range rating of 8 suitable for specified vehicle applications

About the NGK Laser Iridium High Ignitability Spark Plug Line

The Laser Iridium High Ignitability Spark Plug line from NGK focuses on delivering improved ignition performance through the use of iridium and platinum electrode materials. This combination enhances spark efficiency and electrode longevity, making it suitable for high-performance engines such as those found in BMW and Rolls-Royce vehicles. The 91874 part number represents a specific configuration optimized for these applications.

Technical Details and Application

This spark plug features a copper core center electrode with an iridium tip, providing excellent conductivity and wear resistance. The ground electrode uses a nickel core with a square platinum tip, designed to improve ignitability and combustion stability. The resistor type with 5000 ohms resistance helps minimize electromagnetic interference with vehicle electronics. With a flat seat and precise thread dimensions, the 91874 spark plug ensures proper fitment and sealing in compatible engines.

Compatible Vehicles and Common Use Cases

• Compatible with BMW 550i, 550i GT, 550i GT xDrive, 550i xDrive, 650i, 650i xDrive, 750i, 750i xDrive, 750Li, 750Li xDrive, 760Li, X5, and X6 models
• Compatible with Rolls-Royce Ghost model
• Addresses issues such as misfires, rough idling, poor fuel economy, and hard starting
• Helps maintain smooth engine operation and consistent power delivery

Installation Notes and Tips

Ensure the engine is cool before removing old spark plugs. Use a torque wrench with the specified 14 bi-hex socket size to avoid over-tightening. Verify the pre-gap size of 0.030 inches before installation, although NGK spark plugs typically come pre-gapped. Follow manufacturer torque specifications and installation procedures for the specific BMW or Rolls-Royce model.

Quality Assurance and Warranty

NGK spark plugs are manufactured to strict quality standards to ensure reliable performance and durability. The Laser Iridium High Ignitability Spark Plug 91874 undergoes rigorous testing for fitment and electrical properties. Warranty coverage details should be confirmed with the vehicle manufacturer or authorized NGK distributor.