Autolite 405 Spark Plug

Overview of Autolite Copper Resistor Spark Plug 405

The Autolite Copper Resistor Spark Plug 405 is engineered to deliver reliable ignition performance for select classic and luxury vehicles. Designed with a copper core and resistor technology, this spark plug supports efficient combustion and reduces electrical interference in vehicles like the Bentley Continental, Chevrolet El Camino, and Rolls-Royce Silver Dawn.

• Resistance rating of 5000 ohms for noise suppression
• Tapered ground electrode tip made of nickel for durability
• Copper center electrode core with nickel tip for optimal conductivity
• Removable nut electrical terminal type for easy installation
• Flat seat type with a 0.750 inch reach and 14.0 mm thread diameter
• Short ceramic insulator for heat resistance and insulation
• Pre-gap size of 0.034 inches (0.90 mm) for precise spark gap
• Hex size options: 13/16 inch (21 mm) for compatibility with standard tools

Details on the Copper Resistor Spark Plug Product Line

The Copper Resistor Spark Plug line by Autolite incorporates resistor technology to minimize radio frequency interference while maintaining consistent spark delivery. This line features copper core electrodes that enhance thermal conductivity and improve ignition efficiency. The resistor design helps protect sensitive electronic components in modern and classic ignition systems, making it suitable for vehicles such as the Bentley Continental, Chevrolet El Camino, and Rolls-Royce Silver Dawn.

Technical Description and Attributes

The Autolite 405 spark plug features a single tapered ground electrode made from nickel, which provides durability and consistent spark exposure. The center electrode combines a copper core with a nickel tip, balancing excellent heat dissipation with wear resistance. The flat seat design ensures a secure fit in the cylinder head, while the short ceramic insulator offers reliable electrical insulation and heat resistance. The spark plug’s 0.034 inch pre-gap is factory set to optimize ignition timing and combustion efficiency. Additionally, the removable nut terminal type facilitates straightforward installation and maintenance.

Applications and Problem Solving

• Compatible with Bentley Continental, Chevrolet El Camino, and Rolls-Royce Silver Dawn models
• Reduces ignition system radio frequency interference
• Improves combustion efficiency and engine performance
• Helps prevent misfires and rough idling
• Supports stable spark delivery under various operating conditions

Installation Notes and Tips

Before installation, verify the spark plug gap is set to 0.034 inches (0.90 mm) as specified. Use a 13/16 inch (21 mm) socket wrench for proper tightening. Ensure the flat seat spark plug is threaded carefully to avoid cross-threading. The removable nut terminal allows for easy connection to the ignition wire. It is recommended to replace spark plugs in sets to maintain consistent engine performance.

Quality Assurance and Warranty

Autolite spark plugs are manufactured to meet OEM specifications and undergo rigorous quality control testing. The Copper Resistor Spark Plug 405 is designed for durability and reliable performance in compatible vehicles. Warranty coverage details should be confirmed with the product documentation or supplier.