Richmond Ring and Pinion - 3.73 Ratio - 30 Spline Pinion - 3 Series - 8.875 in - GM 12-Bolt 49-0039-1 R010003YM Threads are 7/16"-14 x 1

Threads are 7/16"-14 x 1

Mercury: Park Lane 66 - 68 7 L Engine

Kits hold torsion arm and stop in place if pinch bolts loosen or breakage occurs

Steel wire rings for the greatest combustion seal strength

titanium retainer for GM Gen III applications with #26915 or #26918 Beehive Valve Springs allows you to gain speed and power because titanium retainers are lighter and stronger than most steel ones

Richmond Ring and Pinion - 3.73 Ratio - 30 Spline Pinion - 3 Series - 8.875 in - GM 12-Bolt 49-0039-1 R010003YM Threads are 7/16"-14 x 1RICHMOND is the leading manufacturer of professional quality, hi performance ring and pinion sets. For over 80 years, the Double Diamond has signified the highest quality gears in the racing industry! GM 12 Bolt Installation Notes: When replacing a 2. 73 3. 90 ratio with a Richmond Hi Performance Ring & Pinion, the carrier must be replaced with a carrier from a stock 4. 10, 4. 56 or 4. 88 ratio. When installing 5. 14 to 6. 14 ring & pinion sets,