DSS Racing FX Series Forged Piston Set

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

1-6840-4075D / 2-6840-4075D / 3-6840-4075D / K1-6840-4075D / K2-6840-4075D / K3-6840-4075D

Overview:

The DSS Racing Gen III Hemi FX Series Forged Piston Set is engineered specifically for the 6.1L SRT8 engines found in Chrysler, Dodge, Jeep, and Ram vehicles. Designed to deliver superior strength and durability, these pistons are ideal for enthusiasts and professional builders seeking to enhance engine reliability and performance under demanding conditions. Whether you are rebuilding or upgrading your small block Mopar Hemi, this piston set offers a precise fit and optimized combustion characteristics to support high-performance applications.

With a 4.075" bore size and a compact 1.21" compression height, these forged pistons provide a perfect balance of lightweight design and robust construction. They are crafted to withstand the rigors of high RPM and boost, making them a trusted choice for street performance, track, and racing builds.

Key Features:

These DSS Racing pistons incorporate advanced design elements and manufacturing techniques to ensure top-tier performance and longevity:

• Compatible with 6.1L SRT8 Gen III Hemi engines from Chrysler, Dodge, Jeep, and Ram
• 4.075" bore diameter for precise cylinder fitment
• Forged construction for enhanced strength and durability
• 1.5cc flat top piston design to optimize combustion chamber volume
• Compact 1.21" compression height for improved piston-to-cylinder clearance
• .927" wrist pin diameter with options for full-floating or press-fit installation
• Ring groove dimensions: 1.2mm top and second rings, 3mm oil ring for effective sealing
• Designed for a 3.578" stroke and 6.243" connecting rod length
• Available in multiple dish volumes to tailor compression ratios (65cc, 74cc, 85cc)

Construction & Design:

DSS Racing utilizes high-grade forged aluminum alloy to manufacture these pistons, ensuring exceptional strength-to-weight ratio and thermal conductivity. The forging process refines the grain structure of the metal, resulting in pistons that resist cracking, scuffing, and deformation under extreme heat and pressure. The flat top design with a slight dish volume allows for precise control over compression ratios, accommodating various tuning and fuel requirements.

The pistons feature carefully engineered ring grooves that maintain optimal ring seal and reduce friction, contributing to improved engine efficiency and longevity. The wrist pin options—either full-floating or press-fit—offer flexibility depending on the builder’s preference and application demands.

Installation & Fitment:

This piston set is designed as a direct fit for most Chrysler, Dodge, Jeep, and Ram 6.1L SRT8 engines equipped with a 4.075" bore. Installation requires standard engine rebuilding procedures, including proper honing and cleaning of the cylinder bores. The pistons accommodate a 3.578" stroke crankshaft and 6.243" connecting rods, matching factory or aftermarket components for seamless integration.

Builders should verify wrist pin fitment and ring end gaps according to their specific engine build and tuning goals. No major modifications are typically necessary, making these pistons a straightforward upgrade or replacement option for performance and durability enhancements.

What's Included:

• Set of four DSS Racing Gen III Hemi FX Series forged pistons
• Wrist pins (full-floating or press-fit options depending on SKU)
• Compression and oil rings installed or supplied separately as per configuration
• Technical specifications and installation guidelines

Ideal For:

This piston set is ideal for automotive enthusiasts, professional engine builders, and racers who demand reliable, high-strength components for their 6.1L SRT8 Mopar Hemi engines. It suits applications ranging from street performance upgrades to competitive motorsports where durability and precise engine tuning are critical. Whether rebuilding a worn engine or upgrading for forced induction and higher power outputs, these DSS Racing pistons provide a solid foundation for enhanced engine performance.

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.