DSS Racing FX Series Gen III Hemi Forged Piston Set

Fits Chrysler, Dodge, Jeep, Ram 6.4L 392 Models

1-6840-4100C / 2-6840-4100C / 3-6840-4100C / K1-6840-4100C / K2-6840-4100C / K3-6840-4100C

Overview:

The DSS Racing FX Series Gen III Hemi Forged Piston Set is engineered specifically for the Chrysler, Dodge, Jeep, and Ram 6.4L 392 HEMI engines. Designed to meet the demands of high-performance builds, these pistons offer exceptional strength and durability for enthusiasts and professional builders alike. Whether you are upgrading your engine for increased power or replacing worn factory components, this piston set delivers reliable performance and precision fitment.

Built to handle the rigors of street, strip, or track applications, these forged pistons provide improved thermal resistance and reduced weight compared to cast alternatives. Their design optimizes combustion efficiency and supports higher compression ratios, making them ideal for maximizing the potential of your 6.4L HEMI engine.

Key Features:

These DSS Racing pistons incorporate advanced engineering and materials to ensure superior performance and longevity. Key features include:

• Compatible with 4.100" bore size for most Chrysler, Dodge, Jeep, and Ram 6.4L 392 engines
• Forged construction for enhanced strength and durability under high stress
• Flat top design with a -1.5cc volume for optimized combustion chamber shape
• Pin diameter of .927" available in full-floating or press-fit configurations
• Ring groove dimensions of 1.2mm/1.2mm/3mm for reliable ring sealing and reduced blow-by
• Designed for a 3.720" stroke and 6.2" connecting rods, matching factory specifications
• Available in multiple compression ratios approximately ranging from 9.41 to 11.63, depending on combustion chamber volume
• Precision machining ensures consistent weight and balance for smooth engine operation

Construction & Design:

The DSS Racing FX Series pistons are crafted from high-grade forged aluminum alloy, providing an optimal balance of lightweight properties and structural integrity. The forging process enhances grain structure, resulting in pistons that resist cracking, scuffing, and thermal fatigue even under extreme operating conditions.

The flat top piston crown with a slight dish (-1.5cc) is engineered to improve combustion efficiency and reduce detonation risk. The pistons are designed to accommodate either full-floating or press-fit wrist pins, allowing flexibility based on engine build preferences. Ring grooves are precision-cut to maintain ring stability and sealing performance, contributing to improved compression and reduced oil consumption.

Installation & Fitment:

This piston set is designed as a direct fit for most Chrysler, Dodge, Jeep, and Ram 6.4L 392 HEMI engines with a 4.100" bore. Installation requires standard engine assembly procedures and may necessitate professional machining to ensure optimal clearances and tolerances. The pistons are compatible with factory stroke and rod lengths, simplifying the rebuild or upgrade process without extensive modifications.

What's Included:

• Set of forged pistons sized for 4.100" bore
• Wrist pins (.927") available in full-floating or press-fit options
• Precision-cut piston rings (1.2mm/1.2mm/3mm)
• Installation instructions and technical specifications

Ideal For:

This piston set is ideal for performance enthusiasts, engine builders, and racers seeking to upgrade or rebuild their 6.4L 392 HEMI engines. It suits applications ranging from street performance to competitive motorsports, where durability and power potential are critical. Whether building a high-compression naturally aspirated engine or a boosted setup, these pistons provide a solid foundation for reliable power gains.

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.