Speedmaster Chevy GM LS 6.780" 10% Underdrive Harmonic Balancer Damper SFI 18.1

The Speedmaster LS harmonic balancer damper is a precision crankshaft accessory engineered for Chevy and GM LS-series engines. This 6.780-inch harmonic balancer features a 10% underdrive ratio and carries SFI 18.1 certification, making it suitable for high-performance and racing applications where controlled vibration damping and reliable operation are critical.

Designed specifically for LS engine platforms, this damper absorbs and dissipates crankshaft vibration to protect internal engine components and extend durability. The underdrive design reduces accessory load on the engine, allowing for improved efficiency in demanding conditions. Whether you're building a street performance engine or preparing for track use, this Speedmaster harmonic balancer delivers the combination of damping performance and safety certification required for serious LS engine builds.

Key Features & Benefits

• LS Engine Fitment: Engineered specifically for Chevy GM LS-series engine platforms.
• 10% Underdrive Ratio: Reduces accessory load for improved engine efficiency and performance.
• SFI 18.1 Certified: Meets SFI Foundation safety and performance standards for high-speed and racing applications.
• Vibration Damping: Absorbs and dissipates crankshaft vibration to protect engine internals.
• 6.780" Diameter: Precision-sized for direct compatibility with LS engine configurations.

Specifications

Ideal Applications

• LS engine street performance builds
• Track and racing engine configurations
• High-performance crate engine assembly
• Engine rebuild and restoration projects