Bosch 8515 Spark Plug

Bosch EVO 8515 Spark Plug Overview

Bosch EVO 8515 is a secondary ignition spark plug built for modern gasoline engines that demand stable ignition under high cylinder pressure and heat. It is engineered for direct-injection and turbocharged applications, including select Kia Forte, Kia Seltos, Hyundai Elantra, Hyundai Sonata, and Hyundai Tucson models.

Key Features

• Iridium center electrode with fine-wire design for consistent spark delivery
• Platinum ground electrode tip with tapered J-gap configuration
• High dielectric strength rated above 45 kV for resistance to irregular combustion events
• Projected ceramic insulator for controlled spark exposure
• Resistor spark plug design with 6,000 ohm resistance
• 12 mm thread diameter, 16 mm hex size, flat seat, and 26.5 mm reach
• Built to Bosch EVO specifications for OE-level fit and performance

Product Details

The Bosch EVO line focuses on reliable ignition performance in modern engines that place greater stress on spark plugs. Part number 8515 uses an iridium center electrode, platinum ground tip, and copper core construction to support stable combustion and long service life. Its improved insulator design and high dielectric strength help it withstand irregular combustion conditions found in advanced turbocharged gasoline direct injection engines. Bosch 8515 is a direct replacement-style spark plug for a wide range of Hyundai and Kia applications, including 2020-2024 Kia Forte, 2021-2023 Kia Seltos, 2017-2022 Kia Soul, 2017-2020 Hyundai Elantra, and 2015-2019 Hyundai Sonata.

This part cross-references no listed interchange numbers in the provided data.

What It Helps Address

• Misfire conditions caused by worn or heat-stressed spark plugs
• Hard starting and inconsistent ignition performance
• Rough idle and hesitation under load
• Combustion instability in turbocharged or direct-injection engines
• Reduced spark efficiency from extended service intervals

Installation Notes

Verify thread diameter, reach, seat type, and heat range before installation. Bosch 8515 uses a 12 mm thread, flat seat, 26.5 mm reach, and 16 mm hex, so matching the engine specification is important for proper sealing and combustion chamber clearance. Check and confirm the pre-gap against the vehicle service information before installation. For best results, install on a cool engine and torque to the manufacturer specification.

Quality Assurance

Bosch develops and manufactures EVO spark plugs to the same quality standards used for original equipment spark plugs. The EVO design is intended to meet the demands of modern turbocharged gasoline direct injection engines while maintaining reliable ignition over a long service life.

Compatible Vehicles

• Fits 2020-2024 Kia Forte, N/A
• Fits 2021-2023 Kia Seltos, N/A
• Fits 2020-2022 Kia Forte5, N/A
• Fits 2017-2022 Kia Soul, N/A
• Fits 2018-2021 Hyundai Kona, N/A
• Fits 2019-2021 Hyundai Veloster, N/A
• Fits 2015-2017 Hyundai Veloster, N/A
• Fits 2017-2020 Hyundai Elantra, N/A
• Fits 2018-2020 Hyundai Elantra GT, N/A
• Fits 2016-2020 Kia Optima, N/A
• Fits 2015-2019 Hyundai Sonata, N/A
• Fits 2016-2018 Hyundai Tucson, N/A
• Fits 2007-2012 Acura RDX, N/A
• Fits 2008-2010 Mitsubishi Lancer, N/A