Coil Spring Conv Rear 13in x 5in 300lb

The Coil Spring Conv Rear 13in x 5in 300lb from SWIFT SPRINGS is a precision-engineered suspension component designed for serious automotive builders and mechanics tackling rear suspension upgrades, lowering kits, and custom chassis work. Whether you're setting up a street rod, performance sedan, or competition vehicle, this conventional coil spring delivers the consistent load support and ride control needed to dial in your suspension geometry. Built for those who demand repeatability and predictability in their suspension tuning, this spring is an essential component for anyone transitioning from stock suspension to a fully optimized chassis setup.

Engineered with a tight helix design and a 300 lb/in spring rate, the Coil Spring Conv Rear 13in x 5in 300lb offers the progressive load characteristics that modern suspension geometry demands. The 13-inch length and 5-inch outer diameter fit standard rear suspension mounting points on a wide variety of platforms, while the 300 lb/in rate provides moderate stiffness ideal for street-performance and weekend track applications without sacrificing ride quality. Constructed from high-grade steel with a protective black powder coat finish, this spring resists corrosion and wear while maintaining its calibrated rate over thousands of compression cycles—critical when you're building a suspension that must perform consistently across varying load conditions.

This rear coil spring suits builders working on independent rear suspension systems, multi-link architectures, and custom chassis designs where OEM springs fall short of performance goals. Mechanics installing lowering kits, adjustable coilover systems, or stand-alone spring-and-damper setups will appreciate the tight helix construction, which minimizes spring oscillation and supports crisp weight transfer. At 15.15 lbs per spring, factor for paired installation on both rear corners; always verify ride height and alignment after installation to ensure proper suspension geometry and tire contact patch alignment. Pair this spring with quality dampers and suspension components rated for equivalent or stiffer spring rates to optimize overall chassis dynamics.