DSS Racing FX Series +4cc Dome Top Forged Piston Set

Chrysler / Dodge / Jeep / Ram 6.4L 392 Gen III Hemi Engines

1-6847-4065C / 2-6847-4065C / 3-6847-4065C / K1-6847-4065C / K2-6847-4065C / K3-6847-4065C

Overview:

The DSS Racing FX Series +4cc Dome Top Forged Piston Set is engineered specifically for Chrysler, Dodge, Jeep, and Ram 6.4L 392 Gen III Hemi engines. Designed to enhance performance and durability, these pistons are ideal for enthusiasts and professional builders seeking to maximize power output while maintaining reliability. Featuring a +4cc dome top design, they provide increased compression ratios suitable for high-performance street and race applications.

These pistons are a direct fit for the 386 Small Block Mopar Hemi Gen III platform, offering a comp height of 1.21 inches and a pin diameter of .927 inches. They accommodate either full-floating or press-fit wrist pins, giving flexibility depending on your engine build preferences.

Key Features:

Built to meet the demands of high-performance Hemi engines, the DSS Racing FX Series pistons offer a range of advanced features:

• +4cc dome top design to increase compression and optimize combustion
• Forged construction for superior strength and durability under extreme conditions
• Compatible with 1.2/1.2/3mm ring groove sizes for reliable sealing and reduced friction
• Stroke compatibility of 3.720 inches and rod length of 6.2 inches for precise engine geometry
• Available in multiple combustion chamber volumes (65cc, 74cc, 85cc) to tailor compression ratios from approximately 9.84 to 12.38
• Designed for Chrysler / Dodge / Jeep / Ram 6.4L 392 Gen III Hemi engines ensuring perfect fitment
• Options for full-floating or press-fit wrist pins to suit different engine assembly methods
• Optimized for both street performance and track use with enhanced thermal and mechanical resistance

Construction & Design:

Each piston in the DSS Racing FX Series is precision forged from high-grade aluminum alloy, delivering an excellent strength-to-weight ratio. The forging process enhances grain structure, resulting in pistons that resist cracking, scuffing, and deformation under high combustion pressures and temperatures. The +4cc dome top shape is CNC-machined to exact specifications, ensuring consistent compression ratios and optimal combustion chamber dynamics.

The pistons feature ring grooves sized at 1.2mm for the top and second rings, and 3mm for the oil ring, balancing oil control with minimal friction. The pin bore diameter of .927 inches supports both full-floating and press-fit wrist pin configurations, allowing builders to customize their setup based on performance goals and engine design.

Installation & Fitment:

This piston set is designed as a direct replacement for Chrysler, Dodge, Jeep, and Ram 6.4L 392 Gen III Hemi engines, making installation straightforward for experienced engine builders. The comp height of 1.21 inches and compatibility with a 3.720-inch stroke crankshaft ensure proper piston-to-valve clearance and ring seal. Depending on your build, you may select either full-floating or press-fit wrist pins to match your connecting rods and assembly preferences.

Proper ring end gap and piston deck clearance should be verified during installation to optimize performance and longevity. These pistons are suitable for both fresh builds and performance upgrades where increased compression and durability are desired.

What's Included:

• Set of forged +4cc dome top pistons (quantity as per engine requirements)
• Compatible wrist pins (full-floating or press-fit options depending on SKU)
• Ring groove machining for 1.2/1.2/3mm ring sets
• Detailed specifications for compression ratio and fitment

Ideal For:

This piston set is perfect for performance enthusiasts, professional engine builders, and racers upgrading or rebuilding Chrysler, Dodge, Jeep, or Ram 6.4L 392 Gen III Hemi engines. Whether you are aiming for higher compression ratios for naturally aspirated builds or preparing the engine for forced induction, these pistons provide the strength and precision needed to handle increased power and stress.

They are well-suited for street performance, drag racing, road racing, and other high-demand motorsport applications where reliability and power gains are critical.

DSS Racing — Founded in 1983 originally as Danny’s Speed Shop, DSS Racing has grown from a small Midwest performance engine shop into a respected name in forged engine components for the high-performance and racing markets. Based in St. Charles, Illinois, DSS is best known for its forged pistons and machined engine parts made in the USA that have been used in championship engines and thousands of builds, blending old-school racing roots with precision manufacturing for enthusiasts and racers alike.