Speedmaster PCE306.1050 4.185" Bore Plasma Moly Piston Ring Set - Zero Gap

The Speedmaster PCE306.1050 is a premium piston ring set engineered for high-performance engine builds and rebuilds. Featuring a 4.185-inch bore diameter with plasma moly coating, this zero-gap ring set delivers superior compression sealing, reduced blow-by, and extended ring life. The 1.5-1.5-3mm ring thicknesses (top, second, and oil control rings) are precision-engineered to maintain optimal pressure and friction characteristics in demanding applications.

Plasma moly-coated rings provide enhanced durability and scuff resistance compared to standard chrome-plated alternatives, making them ideal for naturally aspirated and forced-induction engine applications. The zero-gap design ensures tight sealing from initial startup, eliminating the need for pre-fitting and reducing installation time. This ring set is a go-to choice for engine enthusiasts, machine shops, and professional builders who demand reliability and performance from their piston ring components.

Key Features & Benefits

• Plasma Moly Coating: Advanced surface treatment for superior durability, scuff resistance, and extended service life.
• Zero Gap Design: Pre-engineered for tight sealing without requiring custom gap fitting at installation.
• 4.185" Bore Diameter: Precision-sized for specific engine blocks and applications requiring this exact bore specification.
• Complete Ring Set: Includes top, second, and oil control rings (1.5-1.5-3mm) for full engine rebuild requirements.
• High-Performance Grade: Engineered for street, strip, and competition engine applications with demanding combustion pressures.

Specifications

Ideal Applications

• Engine block rebuilds and machine shop overhauls
• High-performance street engine builds
• Forced-induction and naturally aspirated engine applications
• Competition and drag racing engine assembly