TWIN CAM SERIES

The TWIN CAM Series Exhaust System is a purpose-built exhaust platform engineered for high-output Harley-Davidson® V-twin engines. Designed specifically for all 88–131ci+ Twin Cam combinations, every aspect of the system focuses on maximizing exhaust velocity, improving scavenging efficiency, and supporting stable high-horsepower performance without the compromises commonly found in oversized exhaust systems.

At the center of the system is a true merge collector featuring a precisely engineered 15° convergent angle. This collector design improves exhaust pulse scavenging and cylinder evacuation, resulting in stronger midrange torque, faster throttle response, and improved top-end power delivery.

Twin Cam Series Configurations

124 Series

Designed for engines up to 124ci, this configuration prioritizes strong usable torque and responsive midrange power.

Step-Tuned Primary Sizes:
1.75” → 1.87” → 2.00”

Muffler Configuration:
2.50” perforated core inside a 4.00” outer shell

The smaller primary sizing and 2.50” core help maintain exhaust gas velocity for excellent throttle response, strong midrange torque, and broad usable power while still delivering a deep, aggressive exhaust tone.

131 Series

Built for 131ci and larger engines requiring maximum airflow and high-RPM performance.

Step-Tuned Primary Sizes:
1.87” → 2.00” → 2.12”

Muffler Configuration:
3.00” perforated core inside a 4.00” outer shell

The increased primary volume and larger 3.00” core support the airflow demands of extreme displacement combinations while maintaining efficient scavenging, strong top-end pull, and a hard-hitting exhaust note.

135+ Series

Built for 135ci and larger engines requiring maximum airflow and high-RPM performance.

Step-Tuned Primary Sizes:
1.87” → 2.00” → 2.12”→ 2.25"

Muffler Configuration:
3.00” perforated core inside a 4.00” outer shell

The increased primary volume and larger 3.00” core support the airflow demands of extreme displacement combinations while maintaining efficient scavenging, strong top-end pull, and a hard-hitting exhaust note.

All Twin Cam systems share identical routing, collector placement, and chassis fitment. The only difference is the primary tube sizing and muffler core diameter, allowing each system to be properly matched to engine displacement and performance goals.

Thermal Management

Optional full-length, one-piece heat shields provide clean styling, improved heat management, and added durability while maintaining a smooth, uninterrupted appearance.

Built for Big-Inch Performance

From the step-tuned head pipes and true merge collector to the application-specific muffler designs, the Twin Cam Exhaust System was engineered as a complete performance package for riders pushing Twin Cam performance well beyond factory limits.