Victor 41858CP Plasma-Moly Piston Ring Set Bore - 4.000 8-Cylinder

The Victor 41858CP is a premium plasma-moly piston ring set engineered for 8-cylinder engines with a 4.000-inch (101.6mm) standard bore. Featuring a 1.5mm top compression ring, 1.5mm intermediate ring, and 3.0mm oil control ring, this complete set is built to OE specifications for reliable, long-lasting performance.

Key Features:

• Plasma-Moly Top Compression Ring (UCR): Carbon steel base with plasma-moly facing for reduced friction, improved wear resistance, and fast seating
• Barrel-Faced Contact Area: Compression rings feature a barrel-faced profile for more efficient compression sealing and a CNC-controlled gap chamfer to minimize blow-by
• Reverse-Twist Intermediate Ring (LCR): Cast iron second ring with reverse-twist design for superior groove side sealing, plus taper-face machining to enhance cylinder wall contact
• CP-20 Oil Control Ring (OCR): Stainless steel construction with chrome-faced rails and an exclusive 20-degree ear angle for optimal side sealing in the oil ring groove — simplifies installation and prevents improper seating
• Pre-Lapped for Fast Break-In: Rings are pre-lapped at the factory to seat immediately, virtually eliminating conventional break-in time
• Optimized Ring Tension: Materials, coatings, and tension are all tuned to reduce friction and extend service life

Specifications:

• Bore Size: 4.000 in. (101.6 mm) — Standard
• Top Ring (UCR) Thickness: 1.5mm | Radial Width: 0.155 in.
• Second Ring (LCR) Thickness: 1.5mm | Radial Width: 0.151 in.
• Oil Control Ring (OCR) Thickness: 3.0mm | Radial Width: 0.143 in.
• Top Ring Type: BT-10 (Barrel Top)
• Second Ring Type: RBT-10 (Reverse Barrel Top)
• Oil Ring Type: CP-20
• File Fit: No | Gapless: No | Gas Ported: No
• Cylinders: 8

The Victor 41858CP piston ring set delivers OE-quality fit, form, and function for engine rebuilds requiring a proven, installer-friendly solution. The advanced material stack — plasma-moly top ring, cast iron intermediate ring, and chrome-faced stainless oil ring — addresses the full spectrum of compression sealing and oil control demands in performance and daily-driver applications alike.