NGK Spark Plug Stock # 4888

The NGK Spark Plug Stock # 4888 (IMR9B-9H) is a premium iridium-core spark plug engineered for drivers who demand reliable ignition performance and extended service intervals. Whether you're maintaining a stock engine or running a modified vehicle with higher compression ratios, this NGK spark plug delivers the thermal stability and electrode durability required for consistent combustion across a wide range of driving conditions. Built to OEM standards with NGK's proven manufacturing heritage, the IMR9B-9H is the go-to choice for mechanics and enthusiasts seeking long-life spark plug performance without compromise.

NGK's iridium construction provides a smaller, sharper spark kernel than standard nickel electrodes, resulting in faster, more complete fuel ignition and improved throttle response. The iridium center electrode resists erosion far longer than conventional materials, meaning you'll see extended plug life—typically 20,000 to 30,000 miles or more depending on driving patterns and fuel quality. The ceramic insulator is engineered to handle elevated combustion temperatures in turbocharged, supercharged, or high-compression applications, while the ground electrode design minimizes fouling risk in both rich and lean running conditions. This precision construction translates directly to better fuel economy, easier cold starts, and reduced emissions across your vehicle's operating range.

The IMR9B-9H is suitable for a broad spectrum of automotive applications—from daily drivers and commuter vehicles to modified engines running higher ignition timing. Installation is straightforward with standard spark plug tools; simply verify your vehicle's original equipment specifications and thread pitch before installation. For those upgrading from OEM plugs or running aggressive tuning, NGK's iridium formula provides the thermal margin needed to prevent pre-ignition and detonation. Regular inspection and replacement every 20,000 to 30,000 miles ensures peak engine performance and fuel efficiency. Compact design (1 x 0.85 x 3.45 in) fits standard spark plug wells across domestic and import platforms.