Bump Spring Cup 1/2in 1.280 Cup Step OD

The ALLSTAR PERFORMANCE Bump Spring Cup 1/2in 1.280 Cup Step OD (ALL 64354) is a single-spring bump stop cup engineered for suspension tuning in racing and high-performance vehicle applications. This black anodized aluminum component reduces axle wrap, improves traction off the line, and controls suspension travel during hard acceleration or deceleration events where conventional springs alone cannot manage the forces at play.

Built from aluminum and finished in black anodized coating for corrosion resistance and durability, this bump stop cup features a 1.28-inch ID (inner diameter) and 2-inch OD (outer diameter) with a 0.4-inch height profile. The 0.5-inch through hole accommodates standard mounting hardware, while the integrated 1-inch bump spring provides progressive cushioning. The stepped cup design ensures proper alignment and load distribution, critical for maintaining suspension geometry under extreme conditions where shock absorbers and primary springs reach their limits.

This bump spring cup is designed for drag racing, street rod builds, and performance street applications where suspension components experience repeated stress cycles. Quarter-mile launches, hard cornering, and repeated acceleration events demand precision-engineered bump stops that prevent metal-to-metal contact and suspension damage. The ALLSTAR PERFORMANCE specification ensures compatibility with most rear axle assemblies and suspension systems that use standardized bump stop mounting interfaces.

Weighing just 0.12 lbs, this compact component integrates seamlessly into existing setups without adding unnecessary mass. ALLSTAR PERFORMANCE has established itself as a trusted supplier of racing suspension components for professional and enthusiast builders who demand reliable performance without compromise. Whether you're rebuilding a rear axle assembly or upgrading worn bump stops, this cup delivers proven protection against suspension bottoming and axle hop.