2004.5-2005 LLY Duramax Ported & Polished Cylinder Heads (RH & LH Set)
Unlock the full performance potential of your 2004.5–2005 LLY Duramax 6.6L with these Industrial Injection Ported & Polished Cylinder Heads. Designed for high-performance applications, these fully CNC-ported heads deliver increased airflow, and enhanced power capability for racers, sled pullers, and serious diesel enthusiasts.
Machined using Industrial Injection's state-of-the-art 5-axis CNC cylinder head porting technology, each head is precision engineered to maximize airflow consistency across all ports while maintaining exceptional durability. Fully assembled and ready to install, these heads provide the airflow and reliability needed to support demanding horsepower goals.
Key Features
- Fully CNC ported and polished LLY Duramax cylinder heads
- Precision machined using a 5-axis CNC cylinder head porting machine
- CAD/CAM software-developed port design for maximum consistency
- Diamond honed valve guides
- Unshrouded valves for increased airflow
- High-strength alloy, heat-treated iron-based valve guides
- Premium nickel-based, non-magnetic valve seat inserts
- Multi-angle valve job
- 130 lb valve springs installed
- Fully assembled and ready for installation
- Designed for racing, sled pulling, and high-performance applications
Advanced CNC Porting Technology
Each cylinder head is machined on Industrial Injection's advanced 5-axis CNC porting equipment utilizing proprietary CAD/CAM-developed port designs. This process ensures precise port-to-port consistency while significantly improving airflow compared to factory cylinder heads.
The result is increased airflow efficiency, improved combustion characteristics, and enhanced power potential throughout the RPM range. Whether you're building a competition truck or a high-horsepower street setup, these heads provide the airflow necessary to support your performance goals.
What's Included
- Right-hand LLY ported and polished cylinder head
- Left-hand LLY ported and polished cylinder head
- Fully assembled and ready to install
Not Included
- Gaskets
- Head bolts or studs
- Injectors
- Installation hardware
Vehicle Fitment
2004.5–2005 GM Duramax LLY 6.6L
- Chevrolet Silverado 2500HD
- Chevrolet Silverado 3500HD
- GMC Sierra 2500HD
- GMC Sierra 3500HD
Why Choose Industrial Injection Ported & Polished Heads?
- Fully CNC ported for maximum airflow and consistency
- Built specifically for racing and sled pulling applications
- Premium valvetrain and seat components for long-term durability
- Increased airflow compared to stock cylinder heads
- Ready-to-install assembly saves time and labor
- Manufactured and assembled by Industrial Injection performance experts
Core Return Information
Sold as a matched right-hand and left-hand pair.
To receive full core credit, a good, reusable pair of LLY cylinder heads must be returned. Cores must be free of cracks, excessive warping, or severe damage. Core returns are required within 90 days of purchase.