UMI Performance

UMI Performance — Suspension Components & Handling Upgrades for GM Muscle Cars

UMI Performance has been engineering suspension components for classic GM muscle cars since 1995, building a product lineup focused exclusively on the F-body, A-body, and G-body platforms that define American muscle car performance. By concentrating on a specific set of platforms rather than trying to cover every vehicle on the road, UMI develops suspension components with a depth of application-specific engineering that generalist suspension manufacturers cannot match — correct geometry corrections, correct bushing durometer, and correct component clearances for each specific chassis and the way it's used.

Control Arms

UMI Performance control arms are the foundation of the suspension upgrade lineup, replacing factory stamped steel arms with precision-welded tubular steel or chromoly units that reduce weight, improve geometry, and provide correct mounting points for performance bushings and ball joints. Upper and lower control arm kits are available for 1967–1969 Camaro and Firebird, 1964–1972 GM A-body (Chevelle, El Camino, Skylark, Cutlass), and 1978–1988 G-body (Malibu, Monte Carlo, Cutlass) platforms.

UMI's tubular control arms correct the geometry limitations of the factory design — improving camber curve, caster, and roll center compared to the OEM stamped steel arms. Adjustable upper control arms allow caster and camber adjustment beyond the range of the factory eccentric bolts, providing the alignment capability needed for performance street and track use. Delrin, polyurethane, and spherical bearing bushing options are available depending on the desired balance between compliance and precision for each application.

Subframe Connectors

UMI Performance subframe connectors are one of the most impactful handling upgrades available for classic GM unibody muscle cars, tying the front and rear subframes together through the floor pan to dramatically increase chassis rigidity. Factory GM unibody construction leaves the center section of the floor pan as the only structural connection between the front and rear subframes — a design that allows significant chassis flex under hard cornering, braking, and acceleration loads that degrades handling consistency and structural integrity over time.

UMI subframe connectors are available in bolt-in and weld-in configurations for 1967–1969 Camaro and Firebird and 1964–1972 A-body platforms. Weld-in connectors provide maximum rigidity for dedicated performance and race builds, while bolt-in connectors provide a significant rigidity improvement without permanent chassis modification for street-driven builds where reversibility is preferred.

Sway Bars & End Links

UMI Performance sway bars reduce body roll in corners, improving the flat cornering capability of classic GM muscle cars without the harshness of an overly stiff suspension setup. Front and rear sway bar kits are available in multiple diameters for different levels of roll stiffness, with adjustable end links that allow fine-tuning of the sway bar preload for correct suspension geometry at the installed ride height. Correct sway bar sizing balances front and rear roll stiffness for neutral handling rather than simply stiffening one end of the car.

Torque Arms & Panhard Bars

UMI Performance produces torque arms and panhard bars for GM F-body and G-body applications with torque arm rear suspension. The torque arm controls rear axle pinion angle under acceleration and braking loads, while the panhard bar locates the rear axle laterally. UMI's adjustable torque arm and panhard bar allow correct pinion angle and rear axle centering adjustment for lowered and modified suspension setups where the factory components no longer provide correct geometry.

Complete Suspension Kits

UMI Performance complete suspension kits bundle the control arms, subframe connectors, sway bars, and supporting hardware needed for a comprehensive suspension upgrade in a single purchase. Kit configurations are available for street, street/strip, and autocross/road course use, with component specifications matched to the intended use of the vehicle. Complete kits simplify the upgrade process and ensure correct component compatibility across the entire suspension system.

Common Applications

UMI Performance products are engineered for 1967–1969 Camaro and Firebird, 1970–1981 Camaro and Firebird (second generation), 1964–1972 GM A-body (Chevelle, El Camino, Malibu, Skylark, Cutlass, 442), and 1978–1988 GM G-body (Malibu, Monte Carlo, Cutlass, El Camino). These platforms represent the core of classic GM muscle car performance, and UMI's exclusive focus on them produces a depth of application-specific engineering that directly benefits the builder.