AST Linear Race Springs - 140mm Length x 90 N/mm Rate x 61mm ID - Single

AST Suspension builds some of the most precisely engineered dampers available for performance and competition vehicles. Whether you're building a dedicated track car, a dual-purpose street/track machine, or a show car that needs dialed-in stance and handling, AST's lineup of coilovers and shock absorbers delivers the adjustability and build quality serious drivers demand.Popular UpgradesThe AST 4100 series coilovers are a favorite for street-driven enthusiasts wanting meaningful performance gains without sacrificing ride quality. The 4150 and 5100 series step up to more aggressive damping curves suited to autocross and circuit work. AST also offers remote reservoir setups and custom valving for purpose-built race applications where every tenth matters.Are AST coilovers adjustable for ride height?Yes. AST coilovers feature threaded spring perch adjustment, allowing you to dial in ride height independently of shock travel. Many models also offer rebound and compression damping adjustm...

Coilover springs are the replaceable compression springs that wrap around the shock body in a coilover assembly, determining ride height, spring rate, and the balance between comfort and handling stiffness. Swapping springs is the most direct way to tune a coilover setup for a new application without buying an entirely new system.Popular UpgradesLinear-rate springs in the 6 to 12 kg/mm range are the most popular choice for street performance and track day builds where predictable handling is more important than maximum compliance. Progressive-rate springs that soften on small bumps and stiffen under load are preferred for street cars that need to be both comfortable on rough roads and controlled in hard cornering. ID60 and ID65 springs are the most common inner diameter specifications across popular coilover platforms.What is the difference between linear and progressive coilover springs?A linear spring has a constant rate from full droop to full compression, providing consistent an...

Browse premium coilovers and suspension components including coilover kits, coilover shocks, coilover springs, lowering springs, shock hardware, suspension boots, dampening adjustment components, and performance suspension systems for trucks, SUVs, muscle cars, off-road builds, and street performance vehicles. Shop Top Coilover & Suspension Brands Find trusted suspension brands including Silver's NEOMAX, FOX, QA1, Eibach, ICON Vehicle Dynamics, Bilstein, KW Suspension, Ohlins, Ridetech, Fabtech, and ARB/OME. These brands are known for adjustable coilovers, performance shocks, lift and lowering suspension systems, coilover springs, and suspension hardware for daily driving, off-road use, drag racing, and track-focused builds. Coilovers & Components for Street, Track & Off-Road This collection includes complete coilover kits, front and rear coilovers, coilover springs, shock boots and protective covers, dampening adjustment extenders, suspension hardware kits, lowering spr...

Aftermarket suspension systems improve handling, ride quality, and ride height adjustment beyond what the factory suspension provides. From lowering springs and coilover kits for sport handling to lift kits and leveling kits for truck and SUV off-road capability, quality suspension components transform how a vehicle rides and handles. Popular Suspension Upgrades Popular suspension upgrades include coilover kits for adjustable ride height and damping, sport lowering springs for improved handling and reduced body roll, performance shock absorbers and strut assemblies, sway bar and end link upgrade kits, subframe brace kits, and complete suspension packages for lifted trucks and off-road SUVs. Alignment kits including camber bolts and camber arms are also frequently ordered after ride height changes. What is the difference between coilovers and lowering springs? Coilovers are complete shock and spring assemblies with adjustable ride height set by threading the spring perch on the shock...