DSS Racing FX Series +4cc Dome Top Forged Piston Set

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

1-6847-4100D / 2-6847-4100D / 3-6847-4100D / K1-6847-4100D / K2-6847-4100D / K3-6847-4100D

Overview:

The DSS Racing FX Series +4cc Dome Top Forged Piston Set is engineered specifically for the Chrysler, Dodge, Jeep, and Ram 6.1L SRT8 engines, delivering enhanced performance and reliability. Designed to fit most 6.1L SRT8 models, these pistons are ideal for enthusiasts seeking to upgrade their engine’s durability and compression ratio for improved power output.

Built with precision and attention to detail, this piston set offers a +4cc dome top design that increases the compression ratio, optimizing combustion efficiency. Whether you are rebuilding your engine or upgrading for higher performance applications, these pistons provide a solid foundation for sustained power and longevity.

Key Features:

These forged pistons incorporate advanced design elements and materials to meet the demands of high-performance Mopar Hemi engines:

• Compatible with 378 Small Block Mopar Hemi Gen III engines
• +4cc dome top design for increased compression and power
• Comp height of 1.21 inches for precise piston-to-head clearance
• Pin diameter of .927 inches, available in full-floating or press-fit options
• Ring groove dimensions: 1.2mm top and second rings, 3mm oil ring
• Optimized for a 4.100" bore and 3.578" stroke
• Rod length compatibility of 6.243 inches
• Approximate compression ratios vary by combustion chamber size: 65cc (12.12:1), 74cc (10.84:1), 85cc (9.64:1)
• Durable forged construction for enhanced strength and heat resistance

Construction & Design:

DSS Racing’s FX Series pistons are crafted from high-quality forged aluminum alloy, providing superior strength and thermal conductivity compared to cast pistons. The dome top design increases the compression ratio, improving combustion efficiency and power output without compromising reliability.

The pistons feature precision-machined ring grooves and pin bores to ensure optimal ring seal and wrist pin fitment. The option for full-floating or press-fit pins allows customization based on engine build preferences. This meticulous engineering supports high RPM operation and aggressive driving conditions typical of SRT8 performance applications.

Installation & Fitment:

These pistons are designed as direct replacements for most Chrysler, Dodge, Jeep, and Ram 6.1L SRT8 engines with a 4.100" bore. Installation requires standard engine rebuild procedures, including proper honing and cleaning of the cylinder bores. The choice between full-floating or press-fit wrist pins should be matched to your engine’s specifications and performance goals.

Due to the increased compression ratio, it is recommended to verify compatibility with your engine’s fuel and tuning setup to avoid detonation. Professional installation is advised to ensure optimal performance and longevity.

What's Included:

• Set of forged +4cc dome top pistons (quantity as per engine requirements)
• Wrist pins (full-floating or press-fit, depending on selected option)
• Circlips or retaining hardware for wrist pins

Ideal For:

This piston set is perfect for Mopar enthusiasts and professional engine builders looking to upgrade or rebuild their 6.1L SRT8 engines. It suits applications ranging from street performance to track use where increased compression and durability are desired. Ideal for those aiming to extract more power while maintaining engine reliability under demanding conditions.

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.