Motive Gear 12BC355 Ring and Pinion Gear Set GM 8.875" 12-Bolt 3.55 Ratio

The Motive Gear 12BC355 is a ring and pinion gear set designed for GM 8.875-inch 12-bolt car differentials with a 3.55:1 gear ratio and 30-spline pinion configuration. This gear set features a 1.625-inch pinion diameter and is designed for 3 Series carriers that fit 3.07-3.73 ratios.

Key Features:

• 3.55:1 gear ratio for improved acceleration and performance
• 30-spline pinion shaft design
• Fits GM 8.875-inch (12-bolt) car "C" axle configuration
• 12-bolt ring gear mounting pattern
• Compatible with 3 Series carriers (3.07-3.73 ratio range)
• Precision-manufactured to OEM quality standards

This ring and pinion set is designed for 1965 to 1972 GM passenger car applications, commonly found in classic Chevrolet, Pontiac, Buick, and Oldsmobile muscle cars. Swapping ring and pinion gears is one of the first performance upgrades recommended for drag racing cars, as the higher ratio creates more force and can lower elapsed times while providing improved seat-of-the-pants acceleration. Professional installation and a complete bearing kit are recommended for proper setup and longevity.