22×8.5 / 22×9.5 Forged Three-Piece Wheels for 1977 Pontiac Grand Prix (A-Body) – Brushed Silver Center with Polished Lip, Staggered 5×120.65

Engineering Notes

XINGTU’s engineers want to highlight three details that define this build.

Three-Piece Construction & Deep-Lip Design

The Pontiac Grand Prix 3 piece forged wheels feature a forged aluminum center, separate outer lip and inner barrel, joined by structural assembly bolts. This construction defines the wheel's deep-lip profile while allowing the outer lip and barrel to remain individual components within the assembly.

Five paired spoke groups extend from the center and split toward the rim, with elongated machined slots adding definition to each spoke. The open arrangement balances the substantial 22-inch diameter with a detailed, classic-inspired appearance.

The front wheel weighs 14 kg, while the wider rear wheel weighs 13.9 kg. The separate lip and barrel construction also allows individual components to be serviced or replaced when required.

Brushed Silver Center & Polished Outer Lip

The wheel combines two complementary aluminum finishes. A brushed silver treatment gives the forged center a visible directional grain, while the outer lip features a brushed base refined through polishing for a brighter, more reflective surface.

The contrast is especially noticeable along the spoke edges and the transition into the deep outer lip. Elongated slots expose additional machined surfaces, making consistent brushing and careful finishing important to the overall appearance.

Both finished surfaces receive protective sealing to help preserve their distinct textures and metallic character.

Staggered Dimensions for the 1977 Pontiac Grand Prix

The 1977 Pontiac Grand Prix wheel set features a 22×8.5 front configuration with an ET+6 offset and a wider 22×9.5 rear configuration with an ET−7 offset. Both wheels use a 5×120.65 bolt pattern and 70.3 mm center bore.

The negative rear offset positions the wheel farther outward, contributing to the pronounced rear lip and wider stance. The difference in wheel widths and offsets creates a distinctive front-to-rear profile while maintaining the same paired-spoke design.

These production specifications describe the featured Grand Prix configuration. Mounting hardware, brake clearance, suspension geometry and tire compatibility require verification against the actual vehicle, particularly on modified classic-car builds.

From Design to Delivery

• Front 22×8.5 and rear 22×9.5 dimensions inspected
• ET+6 front and ET−7 rear offsets verified
• 5×120.65 PCD and 70.3 mm center bore checked
• Forged center, outer lip and inner barrel assembly inspected
• Structural assembly bolts torqued and marked
• Radial and lateral runout checked
• Paired-spoke geometry and machined slots inspected
• Brushed silver grain consistency checked
• Outer lip polishing and center-to-lip transitions inspected
• Protective sealing and surface condition checked
• Dynamic balancing completed for each wheel

Result

The completed three-piece wheel set brings a distinctive combination of deep-lip proportions and intricate paired spokes to the 1977 Pontiac Grand Prix. The wider rear wheels create a more pronounced outer lip, while the consistent spoke pattern maintains a balanced appearance between the front and rear.

Brushed silver centers retain the visible texture of the aluminum, contrasting with the brighter polished lips. The separate center, lip and barrel components give the finished wheels their characteristic three-piece construction, with exposed assembly details adding to the overall mechanical appearance.

Building a Colonnade-era Pontiac on large-diameter forged wheels?

XINGTU can develop staggered specifications around your car’s hub data, brake package, suspension setup and tire size, including deep-lip three-piece layouts in brushed, polished or custom colour combinations.

MOQ 1 set, DDP worldwide. Send your vehicle details and current brake and suspension configuration for a free fitment check.

Front & Rear Wheel Specifications

The completed set features 22×8.5 ET+6 front wheels and 22×9.5 ET−7 rear wheels, with a 5×120.65 bolt pattern and 70.3 mm center bore. The dimensions reflect the 1977 Pontiac Grand Prix project, including the wider rear barrel and negative rear offset.

Three-Piece Forged Assembly

A forged aluminum center joins a separate outer lip and inner barrel through structural assembly bolts. The five paired-spoke groups feature elongated machined slots, while the brushed silver center and polished lip create contrasting metallic surfaces. The finished front and rear wheels weigh 14 kg and 13.9 kg respectively.

Vehicle Fitment & Mounting Requirements

The 5×120.65 (5×4.75-inch) bolt pattern differs from 5×120 and must not be treated as interchangeable. The lug-seat specification and load rating require confirmation before installation. Brake, suspension, steering, tire and fender clearances should also be checked against the actual vehicle, especially with the ET−7 rear offset.

1. What Is the Difference Between 5×120.65 and 5×120 Bolt Patterns?

The 5×120.65 PCD corresponds to a 5×4.75-inch bolt circle and differs from the 5×120 pattern used on other vehicles. These specifications are not interchangeable, and the wheel must use the correct mounting pattern and compatible hardware.

2. How Are These Three-Piece Forged Wheels Constructed?

Each wheel combines a forged aluminum center with a separate outer lip and inner barrel. Structural assembly bolts connect the components, creating the distinctive deep-lip construction. The separate lip and barrel can also be serviced or replaced when required.

3. What Finishes Are Used on the Wheel Center and Outer Lip?

The center features a brushed silver finish that retains the visible aluminum grain. The outer lip receives additional polishing for a brighter reflective appearance. Both surfaces are sealed to help preserve their finish.

4. Why Do the Front and Rear Wheels Have Different Offsets?

The front wheels use an ET+6 offset, while the wider rear wheels feature ET−7. These specifications create different mounting positions and outer-lip proportions. Actual clearance depends on the vehicle's suspension, bodywork and tire setup.

5. What Should Be Confirmed Before Installing These Wheels?

Confirm the 5×120.65 bolt pattern, center bore, mounting hardware, lug-seat type and load rating. Check brake, suspension, steering and fender clearance with the selected tires, particularly if the vehicle has undergone modifications.

6. How Long Does Production Take for This Three-Piece Wheel Set?

The recorded production schedule is 50 days, covering component machining, three-piece assembly, brushed silver finishing, outer-lip polishing, sealing and final inspection. Shipping time and any additional design revisions are separate from the production schedule.