Chevy SBC 350 7.250" Internal SFI-Rated Fluid Damper Harmonic Balancer They are made of aluminum

They are made of aluminum and feature a natural finish

capable of withstanding valve spring load up to 600lbs

They're designed with performance in mind

The cells have foam in the base to prevent fuel aeration

Designed to fit most applications with dual bolt patterns for Borg & Beck and Long-style clutch assemblies

Chevy SBC 350 7.250" Internal SFI-Rated Fluid Damper Harmonic Balancer They are made of aluminumSpeedmaster harmonic balancers are crafted from high quality steel and feature a tuned elastomer for optimal engine performance. They include a strong bonding process, easy to read timing marks, and an advanced design to absorb engine vibrations, extending the life of the crankshaft and bearings for enhanced power and torque.