DSS Racing FX Series Forged Piston Set

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

1-6845-4055D / 2-6845-4055D / 3-6845-4055D / K1-6845-4055D / K2-6845-4055D / K3-6845-4055D

Overview:

The DSS Racing FX Series Forged Piston Set is engineered specifically for high-performance applications in Chrysler, Dodge, Jeep, and Ram vehicles equipped with the 6.1L SRT8 engine. Designed to replace factory cast pistons, these forged pistons provide superior strength and durability, making them ideal for enthusiasts looking to enhance engine reliability under demanding conditions. Whether you are building a street performance engine or a track-ready powerplant, this piston set offers the precision and quality needed to withstand increased power and boost levels.

These pistons are compatible with the 370 Small Block Mopar Hemi Gen III platform and are tailored to fit engines with a 4.055" bore size. Their compact design and optimized dish volume help maintain efficient combustion and compression ratios, supporting both naturally aspirated and forced induction setups.

Key Features:

Built to meet the rigorous demands of performance engines, the DSS Racing FX Series Forged Pistons include the following features:

• Precision forged construction for enhanced strength and fatigue resistance
• Comp height of 1.21" for optimal piston-to-head clearance
• 18cc dish top design to control compression and support various combustion chamber sizes
• .927" wrist pin diameter with options for full-floating or press-fit configurations
• Ring groove dimensions of 1.2mm/1.2mm/3mm to accommodate high-performance piston rings
• Compatible with a 3.578" stroke and 6.243" connecting rods
• Available in multiple dish volumes (65cc, 74cc, 85cc) to tailor compression ratios from approximately 7.8:1 to 9.29:1
• Designed for use in the Mopar 6.1L SRT8 engine family, ensuring precise fitment and performance

Construction & Design:

DSS Racing utilizes advanced forging techniques to produce pistons that offer superior mechanical properties compared to standard cast pistons. The FX Series pistons are crafted from high-grade aluminum alloy, providing an excellent balance of strength, weight, and thermal conductivity. This construction reduces reciprocating mass while maintaining the durability needed for high RPM and high-load conditions.

The pistons feature a carefully engineered dish top to optimize combustion chamber shape and compression ratio, enhancing power delivery and efficiency. The wrist pin bore is designed to accept either full-floating or press-fit pins, allowing flexibility depending on engine build preferences. Additionally, the ring grooves are machined to tight tolerances to ensure proper ring sealing and longevity under extreme conditions.

Installation & Fitment:

This piston set is designed to fit most Chrysler, Dodge, Jeep, and Ram vehicles equipped with the 6.1L SRT8 engine, specifically those with a 4.055" bore. Installation requires standard engine rebuild procedures, including proper honing and cleaning of the cylinder bores. Depending on the wrist pin option selected, either full-floating or press-fit pins can be installed to match your engine’s configuration.

Professional installation is recommended to ensure correct piston ring end gaps, wrist pin alignment, and torque specifications. These pistons are compatible with the factory stroke and connecting rod length, making them a direct upgrade for performance rebuilds or engine refreshes.

What's Included:

• Set of forged pistons sized for 4.055" bore
• Wrist pins (full-floating or press-fit, depending on selection)
• Piston rings compatible with 1.2/1.2/3mm groove dimensions
• Installation instructions and technical specifications

Ideal For:

This piston set is ideal for automotive enthusiasts, engine builders, and racers who demand enhanced durability and performance from their Mopar 6.1L SRT8 engines. Whether upgrading for increased horsepower, forced induction, or extended engine life under high-stress conditions, the DSS Racing FX Series Forged Pistons provide a reliable foundation for serious builds.

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.