NGK 4421 Spark Plug

Reliable Ignition with NGK V-Power Spark Plug 4421

The NGK V-Power Spark Plug 4421 (Bkr4e) delivers consistent ignition performance with durable materials and precise design. Engineered for vehicles requiring a flat seat type and a 14mm thread diameter, this spark plug supports efficient combustion and reliable starts.

• Resistance: 5000 ohms for optimal electrical performance
• Ground Electrode Tip and Configuration: Standard design with a single ground electrode
• Core Materials: Copper center electrode with nickel tip and nickel ground electrode core
• Pre-gap Size: 0.036 inches for precise spark gap
• Hex Size: 5/8 inch for easy installation
• Insulator Height: 50.50 mm for proper insulation
• Manufacturer Heat Range: 4, suitable for moderate engine temperatures
• Seat Type: Flat for secure fitment
• Reach: 0.75 inches to match specific engine requirements
• Electrical Terminal Type: Non-removable nut for stable connection

About the NGK V-Power Spark Plug Line

The V-Power Spark Plug line by NGK is designed to provide reliable ignition performance with a focus on durability and consistent spark delivery. This product line incorporates quality materials such as copper and nickel to ensure stable electrical conductivity and resistance to wear. The 4421 part number fits within this line, offering a balance of heat range and electrode design suitable for a variety of automotive applications.

Technical Details and Application

The NGK 4421 spark plug features a copper core center electrode with a nickel tip, enhancing conductivity and durability. The single ground electrode with a standard tip design ensures a stable spark path. With a resistance of 5000 ohms, it helps reduce electrical noise and interference. The flat seat and 14mm thread diameter make it compatible with many vehicles requiring these specifications. The pre-gap of 0.036 inches is factory set to optimize ignition timing and combustion efficiency.

Common Uses and Problem Solving

• Restores proper ignition in engines experiencing misfires
• Improves cold start performance in compatible vehicles
• Reduces engine hesitation and rough idling
• Maintains consistent spark delivery under normal operating conditions
• Helps prevent fouling in engines with moderate heat ranges

Installation Notes and Tips

Ensure the spark plug gap is checked before installation, although the pre-gap is factory set at 0.036 inches. Use a 5/8 inch socket for installation and torque to manufacturer specifications to avoid damage. The non-removable nut terminal type requires compatible ignition wire connectors. Confirm compatibility with your vehicle’s make and model, especially regarding thread diameter and reach.

Quality Assurance and Warranty

NGK spark plugs, including the V-Power 4421, are manufactured to meet strict quality standards for ignition components. While specific warranty details are not provided here, NGK products typically come with manufacturer-backed quality assurance to ensure reliable performance and durability.