UMI Performance Coil Spring / Tie Rod Sleeve / Sway Bar Kit

UMI Performance Coil Springs, Tie Rod Sleeves & Sway Bar Kits

When it comes to tightening up a classic GM muscle car's front-end geometry and body roll characteristics, few brands bring the depth of focus that UMI Performance does. Founded in Philipsburg, Pennsylvania in 2002, UMI has built its entire reputation around solving real-world handling problems for enthusiasts — and their lineup of coil springs, tie rod sleeves, and sway bar kits is a direct expression of that mission.

Every component is designed and manufactured in-house. UMI Performance proudly designs and manufactures its entire product line within its Pennsylvania facility, which features CNC machining, CNC laser cutting, MIG and TIG welding, and powder coating. This end-to-end control over production means every spring rate is dialed in and every billet sleeve is machined to exacting tolerances — not outsourced and not compromised.

What Sets UMI's Kits Apart

UMI's approach to coil spring and sway bar kits goes beyond simple replacement. Their front lowering coil springs — such as the 6452F for the 1963–1987 GM C10 — are engineered for a specific drop (typically 2") with rates tuned for both street driveability and improved cornering response. Rather than a generic "universal" spring, each application targets a precise platform.

The billet tie rod adjusting sleeves, like the 6102 for 1960–1964 GM C10/C15 trucks, are machined from billet aluminum — a significant upgrade over stamped steel OEM sleeves that are prone to corrosion and flex under load. These sleeves offer improved toe adjustment precision and better long-term durability, making them a go-to choice when rebuilding a front steering system.

UMI's tubular and solid sway bars round out this category with meaningful anti-roll upgrades. Their front sway bars for the GM C10 — available in tubular configurations up to 1-3/8" diameter — and adjustable rear sway bars for the C10 (such as the 6443 at 1" adjustable) allow tuners to dial in front-to-rear roll balance for their specific build goals. UMI also offers solid 32mm front sway bars for GM A-Body, B-Body, and G-Body platforms — addressing body roll on popular muscle cars like the Chevelle, Monte Carlo, and Regal.

Platform Coverage

UMI focuses on the platforms that matter most to muscle car builders. Their coil spring, tie rod sleeve, and sway bar kits span a wide range of classic and late-model GM applications:

• 1960–1987 GM C10/C15 trucks (front and rear)
• 1978–1988 GM G-Body (Malibu, El Camino, Monte Carlo, Regal)
• 1964–1972 GM A-Body (Chevelle, GTO, Cutlass)
• 1982–2002 GM F-Body (Camaro, Firebird, Trans Am)
• 1978–1996 GM B-Body (Caprice, Impala SS, Roadmaster)

UMI also installs and tests every chassis and suspension component it makes to ensure real-world performance matches the engineering spec — a level of validation that sets them apart from catalog-only brands. Whether you're building a pro-touring street car or a dedicated autocross competitor, UMI's coil springs, tie rod sleeves, and sway bar kits provide a foundation of confidence in the suspension setup.