DSS Racing Gen III FX Series Forged Piston Set

Fits Most Chrysler / Dodge / Jeep / Ram 6.1L SRT8 Models

1-6840-4090 / 2-6840-4090 / 3-6840-4090 / K1-6840-4090 / K2-6840-4090 / K3-6840-4090

Overview:

The DSS Racing Gen III FX Series Forged Piston Set is engineered specifically for the 6.1L SRT8 engines found in Chrysler, Dodge, Jeep, and Ram vehicles. Designed to replace factory pistons, this set offers enhanced strength and durability for high-performance applications. Whether you are building a street performance engine or a track-ready powerplant, these pistons provide the reliability and precision needed to handle increased horsepower and boost levels.

These forged pistons are ideal for enthusiasts and professional builders seeking to improve engine longevity while maintaining factory-like dimensions and clearances. Their compatibility with the 376 Small Block Mopar Hemi Gen III platform ensures a direct fit with minimal modifications.

Key Features:

Built with advanced forging technology and engineered for optimal performance, the DSS Racing Gen III FX Series pistons deliver a range of benefits:

• Compatible with 4.090" bore applications on most Chrysler, Dodge, Jeep, and Ram 6.1L SRT8 engines
• Forged construction for superior strength and resistance to detonation
• Flat top design with a -1.5cc dish for precise combustion chamber volume control
• Compression height of 1.21" to maintain proper deck clearance and piston-to-valve clearance
• .927" wrist pin diameter with options for full-floating or press-fit configurations
• Ring groove dimensions of 1.2mm top and second rings, and 3mm oil ring for effective sealing and oil control
• Designed to work with a 3.578" stroke and 6.243" connecting rods for balanced performance
• Available in multiple combustion chamber volume options (65cc, 74cc, 85cc) to tailor compression ratios from approximately 9.06:1 to 11.2:1
• Precision machining ensures consistent fitment and performance across all pistons in the set

Construction & Design:

The DSS Racing Gen III FX Series pistons are crafted from high-quality forged aluminum alloy, providing an excellent strength-to-weight ratio. The forging process enhances the grain structure of the metal, resulting in pistons that can withstand the rigors of high cylinder pressures and temperatures common in performance engines.

The flat top piston design with a slight dish (-1.5cc) optimizes combustion efficiency and helps control compression ratios for various tuning needs. The pistons feature carefully engineered ring grooves and wrist pin bores to ensure durability and reduce friction. Options for full-floating or press-fit wrist pins allow builders to customize installation based on engine requirements.

Installation & Fitment:

This piston set is designed for direct fitment in most Chrysler, Dodge, Jeep, and Ram 6.1L SRT8 engines using a 4.090" bore. The pistons maintain factory dimensions for compression height and wrist pin size, simplifying installation and minimizing the need for additional machining or modifications. Proper ring end gap and clearance checks are recommended during assembly to ensure optimal performance and longevity.

Whether upgrading a stock rebuild or assembling a high-performance engine, these pistons provide a reliable foundation for increased power and durability.

What's Included:

• Set of forged pistons sized for 4.090" bore
• Wrist pins (.927") with options for full-floating or press-fit installation
• Precision-machined ring grooves compatible with 1.2mm top and second rings, and 3mm oil rings
• Comprehensive documentation for installation and specifications

Ideal For:

This piston set is perfect for engine builders, performance enthusiasts, and professional shops upgrading or rebuilding 6.1L SRT8 engines. It suits applications ranging from street performance to track use, where enhanced strength, reliability, and precise combustion control are critical. The multiple combustion chamber volume options allow tuning for various compression ratios to match fuel types and power goals.

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.