Denso Iridium Spark Plug 3273

Denso 3273 Spark Plug, with advanced manufacturing processes, meets OEM quality standards and is a trusted supplier in the automotive aftermarket.

• Engineered to withstand extreme conditions, ensuring reliable performance over time.
• Designed with an advanced electrode for more efficient ignition.
• Backed by Denso's commitment to high-quality automotive engineering and performance.
• Recognized as one of the best spark plugs available for superior reliability.
• Offers a smoother ride with quicker acceleration and stable idling.

Iridium power and ignitability advantage

DENSO iridium spark plugs are engineered to achieve higher ignitability by using a finely designed iridium center electrode and a specially shaped ground electrode. Compared with normal plugs, the iridium tip requires lower spark voltage, allowing the flame kernel to form faster and more consistently. This directly improves spark performance during cold starts, acceleration, and high-load driving conditions. The result is smoother throttle response, improved acceleration, and more stable power output across a wide range of vehicles, including luxury vehicles and performance-focused models.

Precision electrode design and thermal control

Each plug uses DENSO’s patented iridium alloy combined with a laser welding process to ensure exceptional strength at the electrode tip. The iridium center electrode and optimized ground electrode geometry help maintain a precise spark gap over time. High thermal conductivity allows heat to dissipate efficiently, reducing the risk of misfire and preventing electrode wear. This design supports long-term durability while maintaining consistent ignition performance throughout the service life.

Insulator structure and voltage stability

The purified alumina powder insulator provides excellent electrical insulation and heat resistance. A five-rib insulator design helps prevent flashover by extending the surface leakage path. Combined with a gas-tight seal, this structure stabilizes spark voltage and protects internal components from combustion gases. These features work together to ensure reliable ignition under high pressure, high temperature, and extended driving conditions.

Installation compatibility and application coverage

DENSO iridium spark plugs are manufactured to precise thread, hex size, and torque specifications, reducing the risk of cross threading or seizing during installation and removal. They are widely used across Toyota, Honda, GM, Mitsubishi, and other vehicle platforms, as well as selected powersports and non-automotive applications. Each plug is designed to fit shop parts standards and OEM replacement requirements, ensuring consistent compatibility across supported models.