Gen III Hemi 185cc LH Cyl Head 69cc Assembled

The AIR FLOW RESEARCH Gen III Hemi 185cc LH Cylinder Head is a precision-engineered assembled casting designed for Mopar Gen III Hemi engine builds requiring optimized flow characteristics and chamber volume. This left-hand (driver side) cylinder head features a 185 cubic centimeter intake runner volume paired with a 69 cubic centimeter combustion chamber, making it suitable for both street and competition applications where intake efficiency directly impacts horsepower output and throttle response.

Specifications include 2.050-inch and 1.590-inch valve diameters (intake and exhaust respectively) with 1.290-inch valve spring diameter, straight spark plug configuration, and aluminum construction. The 185cc intake port volume represents a balance point for street engines—large enough to support high RPM flow without creating low-speed signal loss that reduces torque development. AFR's casting process and assembly ensure consistent port geometry critical for matching paired heads and maintaining combustion balance across all cylinders. The 69cc chamber volume suits stroker and naturally aspirated builds requiring controlled compression ratios in modern fuel environments.

This head is selected by builders targeting Hemi powerplants from truck, muscle car, and marine applications where durability and repeatable performance matter. Operators in high-performance engine assembly rely on AFR heads for documented flow bench numbers and straightforward bolt-on installation. The assembled condition eliminates valve job preparation and spring seating, reducing machine shop lead time and installation complexity for shops running tight build schedules.

Gen III Hemi cylinder heads must match combustion chamber volume, port volume, and valve configuration across a complete set to maintain detonation control and cylinder-to-cylinder balance. The 185cc/69cc combination from AFR occupies the mid-range tuning window for street-strip applications—aggressive enough for cam profiles pushing 6500 RPM yet conservative enough for daily-use compression ratios. Weight at 22 pounds per head allows accurate ballast calculations during engine balancing work. Verify compatibility with your specific Hemi block variant (2003+, truck vs. car platform) before ordering.