A Modern Chassis for the 1947–1954 Chevrolet 3100 and GMC 100

Vehicle-Specific Development

The ACD 3100 chassis begins with the requirements of the 1947–1954 Chevrolet 3100 and GMC 100 platform. The 116-inch wheelbase establishes the basic vehicle architecture, while the suspension, chassis, and component packaging are developed together around the truck.

Rather than choosing track width, control-arm locations, ride height, or suspension geometry independently, ACD evaluates how each decision affects the complete vehicle. Weight distribution, suspension travel, steering geometry, braking, drivetrain placement, wheel and tire clearance, ground clearance, body packaging, and chassis structure all influence the final design.

This approach allows the suspension geometry and chassis dimensions to be optimized together, with the goal of achieving excellent ride quality, responsive handling, precise steering, strong braking, stability, and predictable behavior in real-world driving.

The vehicle defines the requirements. The chassis and suspension are developed around them.

Packaging is developed around the complete vehicle rather than treated as a collection of separate systems. Engine and transmission placement can influence weight distribution, firewall clearance, driveline angles, exhaust routing, steering clearance, and available suspension space. Rear suspension packaging must work with the bed, frame structure, differential, axles, exhaust, fuel system, and the wide rear wheel and tire package.

Ride height is approached the same way. The goal is not simply to make the truck sit low. Running-board height, ground clearance, suspension travel, axle position, wheel and tire clearance, and chassis structure all have to work together at the intended ride height.

The development vehicle also gives ACD the freedom to evaluate these relationships with the actual body in place. CAD establishes the geometry and packaging, while the physical truck provides the final envelope that the chassis must fit and function within.

Clearance for Modern Components

Engineered for generous wheel and tire packaging, accommodating modern brake systems and wider wheel choices without compromise. The design ensures optimal clearance and integration for a contemporary stance.

Suspension Architecture

C7-Based Front and Rear Suspension

The ACD 3100 C7 Development Program uses C7 Corvette front and rear aluminum uprights as the foundation for a completely vehicle-specific suspension system. The uprights provide modern hub and bearing assemblies, brake mounting, wheel-speed sensing capability, and proven serviceable components, while giving ACD the freedom to develop the surrounding suspension around the requirements of the 1947–1954 Chevrolet and GMC pickup platform.

One of the most important characteristics of the C7 upright is the substantial separation between the upper and lower ball joints. That separation provides considerable freedom when determining control-arm lengths, angles, and chassis pickup locations. Rather than inheriting the suspension geometry of another vehicle, ACD can develop the camber curve, roll-center behavior, caster, steering geometry, suspension travel, and wheel and tire packaging as part of the 3100 chassis.

Front suspension geometry is being developed together with steering rack placement and control-arm pickup locations so that steering behavior, bump steer, Ackermann, suspension travel, tire clearance, and chassis packaging can be evaluated as a complete system. Coilover placement and motion ratio are also developed as part of the suspension geometry rather than simply locating the shock wherever packaging allows.

At the rear, the C7 upright provides the foundation for a fully independent suspension developed specifically for the truck. The rear control-arm geometry, coilover placement, motion ratio, axle position, and chassis structure are being developed around the desired ride height, suspension travel, vehicle weight, and wide rear wheel and tire package. A Dutchman 9-inch independent rear center section and custom-length axles provide a strong, serviceable drivetrain foundation without dictating the suspension geometry.

Using modern front and rear uprights also provides access to a broad range of OEM and aftermarket brake components. Brake sizing, wheel clearance, tire capability, vehicle weight, and intended street performance can therefore be considered together rather than treating the brakes as an isolated component choice.

The result is a suspension architecture in which the uprights are only the starting point. Control-arm geometry, chassis pickup points, steering, coilover motion ratios, brakes, track width, ride height, wheel and tire packaging, and chassis structure are all developed together for the 3100 platform.

The C7 uprights establish the foundation. ACD determines the geometry around them.

The objective is not maximum performance at the expense of everything else. The suspension is being developed for the combination that matters in a high-end street-driven restomod: excellent ride quality, predictable handling, responsive steering, strong braking, usable suspension travel, high mechanical grip, stability, and confidence at real-world speeds.

Development, Fabrication & Validation

From CAD to Production

The ACD 3100 C7 Development Program moves from digital suspension and chassis development into a physical prototype built using the same processes intended for future production.

Suspension geometry and vehicle packaging are developed in CAD first, allowing control-arm pickup points, steering placement, coilover locations, drivetrain position, wheel and tire clearances, chassis structure, and component packaging to be evaluated together before steel is cut.

Once the design reaches the fabrication stage, the chassis rails, crossmembers, suspension mounts, and other structural components are translated into CNC-cut parts. Purpose-built fixtures locate critical chassis dimensions and suspension pickup points in three dimensions during assembly, providing a repeatable foundation for accurate fabrication.

The prototype chassis will then be assembled with the suspension, steering, brakes, drivetrain, wheels, and tires before being fitted beneath the development truck. This allows the digital design to be checked against the actual vehicle and provides an opportunity to evaluate component clearances, suspension travel, steering range, wheel and tire clearance, serviceability, and overall packaging.

Physical testing follows prototype assembly. Ride quality, handling balance, steering response, braking behavior, suspension travel, and real-world drivability can then be evaluated with the complete vehicle operating as a system. Information gathered during testing will be used to refine the chassis and suspension before the design is finalized for production.