DSS Racing FX Series Forged Flat Top Piston Set

Chrysler / Dodge / Jeep / Ram 6.1L SRT8

1-6840-4125 / 2-6840-4125 / 3-6840-4125 / K1-6840-4125 / K2-6840-4125 / K3-6840-4125

Overview:

The DSS Racing FX Series Forged Flat Top Piston Set is engineered specifically for the Chrysler, Dodge, Jeep, and Ram 6.1L SRT8 models featuring the Gen III Hemi engine platform. Designed to replace factory pistons, this set offers superior strength and durability for high-performance applications. Ideal for enthusiasts and professional builders seeking enhanced engine reliability and efficiency, these pistons provide a solid foundation for increased power and longevity under demanding conditions.

Crafted to exacting specifications, the FX Series pistons maintain optimal compression ratios while accommodating various combustion chamber volumes, ensuring compatibility with a range of build configurations. Whether upgrading a street machine or building a race-ready engine, these pistons deliver consistent performance and improved thermal management.

Key Features:

Built to meet the rigorous demands of high-performance Mopar engines, the DSS Racing FX Series pistons incorporate advanced design elements and materials:

• Forged construction for exceptional strength and durability
• Flat top design with a -1.5cc dish for optimized combustion efficiency
• Comp height of 1.21 inches for precise deck clearance and piston-to-head clearance
• .927-inch wrist pin diameter with options for full-floating or press-fit installation
• Ring groove dimensions of 1.2mm/1.2mm/3mm to accommodate high-performance piston rings
• Compatible with 3.578-inch stroke crankshafts and 6.243-inch connecting rods
• Available in multiple combustion chamber volumes (65cc, 74cc, 85cc) to tailor compression ratios from 9.2:1 up to 11.36:1
• Precision machining ensures tight tolerances and reliable fitment

Construction & Design:

The FX Series pistons are forged from premium-grade aluminum alloy, providing an optimal balance of lightweight strength and heat dissipation. The flat top profile promotes efficient combustion and reduces the risk of detonation, while the carefully engineered dish volume allows builders to fine-tune compression ratios to match specific engine setups. The wrist pins are designed for either full-floating or press-fit installation, offering flexibility depending on engine build preferences. Ring grooves are precisely cut to accommodate high-performance rings, ensuring excellent sealing and reduced blow-by.

Each piston undergoes rigorous quality control and finishing processes to guarantee durability and performance under extreme operating conditions typical of SRT8 and other high-output Mopar engines.

Installation & Fitment:

This piston set is designed as a direct fit replacement for most Chrysler, Dodge, Jeep, and Ram 6.1L SRT8 Gen III Hemi engines. Installation requires standard engine rebuild procedures, including proper honing of cylinder walls and careful measurement of piston-to-cylinder clearance. Depending on the wrist pin option selected, either full-floating or press-fit installation methods can be employed. No major modifications are necessary, making these pistons an excellent upgrade for both rebuilds and performance enhancements.

What's Included:

• Set of forged flat top pistons (quantity as required for engine)
• Wrist pins (.927" diameter) compatible with full-floating or press-fit installation
• Detailed specifications for compression ratios and piston dimensions

Ideal For:

The DSS Racing FX Series Forged Flat Top Pistons are ideal for performance enthusiasts, engine builders, and racers who demand reliable, high-strength components for their 6.1L Gen III Hemi engines. Whether upgrading a street SRT8 for improved durability or building a competition engine requiring precise compression tuning, these pistons offer a versatile and robust solution.

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.