Speedmaster PCE291.1012 Chevy 383 400 6.610" External Balanced Harmonic Balancer SFI 18.1

The Speedmaster PCE291.1012 is an external-balanced harmonic balancer engineered for Chevy 383 and 400 big-block engines. With a 6.610-inch diameter and SFI 18.1 certification, this balancer is designed to handle high-performance and racing applications where reliability and precision damping are critical. The external-balanced design ensures compatibility with engines that require this specific damper configuration for proper crankshaft operation.

This harmonic balancer effectively reduces vibration and absorbs harmful harmonic oscillations generated during engine operation, protecting the crankshaft, block, and drivetrain components from fatigue damage. The SFI 18.1 rating confirms it meets safety standards for sanctioned racing environments. Whether you're building or rebuilding a 383 or 400 engine for street or strip use, this balancer delivers proven damping performance and durability in a purpose-built package.

Key Features & Benefits

• External Balanced Design: Optimized for Chevy 383/400 engines requiring external balancing configuration.
• 6.610" Diameter: Precise OEM-compatible size for proper fitment and crankshaft engagement.
• SFI 18.1 Certified: Meets SFI safety specifications for sanctioned racing and high-performance use.
• Harmonic Damping: Reduces crankshaft vibration and protects engine internals from oscillation damage.
• Speedmaster Quality: Built with precision engineering for reliability in demanding performance applications.

Specifications

Ideal Applications

• High-performance big-block Chevy engine builds and rebuilds
• Racing engines in sanctioned competition
• Drag racing and street performance applications
• Engine restorations requiring original-spec external balancing