Wiseco GLS20 Dimpled Oil Rail Support 3.365-3.406 in. Bore

The Wiseco GLS20 Dimpled Oil Rail Support is a precision piston ring groove accessory engineered for high-performance engine builds where the piston oil ring groove intersects the wrist pin bore. This condition is common in short-compression-height pistons resulting from large strokes or long rod lengths, making oil rail supports an essential component for a reliable ring seal.

Key Features:

• Bore Range: Fits 3.365 in. to 3.406 in. (85.47 mm – 86.51 mm) bore diameter
• Dimpled Design: Features a special anti-rotation dimple that locks the oil rail in place, positioned directly in line with the piston pin
• Spring Steel Construction: Made from durable spring steel and installed against the bottom sill of the oil ring groove
• Groove Compatibility: For use only with pistons that have an oil ring groove machined 0.030 in. wider than the oil ring
• Prevents Oil Ring Intrusion: Bridges the wrist pin opening to prevent the oil ring from protruding through the pin bore
• Sold Individually: Package includes one (1) oil rail support

Proper installation requires orienting the dimple downward and over the wrist pin hole so the end gap sits 90 degrees from the wrist pin. Wiseco oil rail supports are an OEM-replacement and upgrade solution for performance pistons requiring this critical ring groove modification.