Mangum Racing MR 229 Cylinder Head LS 4.8 / 5.3 4 Bolt Casting

Mangum Racing MR 229 Cylinder Head LS 4.8 / 5.3 4-Bolt Casting

The Mangum Racing MR 229 Cylinder Head is purpose-built for small-bore LS engine combinations that demand maximum airflow without sacrificing durability or factory valve geometry. Featuring a 229cc fully CNC-ported intake runner and premium 4-bolt LS casting, the MR 229 was designed specifically around the 4.8L and 5.3L LS platform while providing compatibility with all larger cathedral-port LS engines. Unlike traditional LS6-based cylinder heads, the MR 229 is an all-new casting engineered from the ground up to maximize airflow, strength, and combustion efficiency.

Designed around a 2.02-inch intake and 1.57-inch exhaust valve package, the MR 229 clears every LS bore from the 4.8L's 3.780-inch bore and larger, making it an ideal choice for naturally aspirated, turbocharged, supercharged, and nitrous-assisted applications. Manufactured entirely in-house using Centroid 5-axis CNC machining centers and Newen seat and guide equipment, every cylinder head is CNC ported, hand blended, inspected, and assembled in small batches to deliver exceptional consistency. Supporting well over 1,500 horsepower when paired with the proper short block and induction system, the MR 229 combines OEM valve geometry with race-proven airflow and premium valvetrain components.

Key Features

• Designed specifically for 4.8L and 5.3L LS engines while fitting all larger cathedral-port LS engines.
• Premium 4-bolt LS casting with increased deck thickness.
• Ground-up cylinder head design—not an LS6 casting copy.
• Fully CNC-ported 229cc intake runners.
• Fully CNC-machined combustion chambers and exhaust ports.
• 97cc CNC exhaust ports.
• 62cc CNC combustion chambers.
• OEM 15-degree LS valve angle and factory valve spacing.
• 2.02-inch stainless steel intake valves.
• 1.57-inch stainless steel exhaust valves.
• Bronze valve guides.
• PAC dual valve spring package.
• Titanium retainers.
• Viton valve seals.
• 1.250-inch steel spring seats.
• Supports naturally aspirated, turbocharged, supercharged, and nitrous combinations.
• Capable of supporting 1,500+ horsepower with the proper combination.
• Small-bore design clears all LS engine bores from 3.780 inches (4.8L) and larger.

Airflow Performance (SuperFlow Flow Bench)

Specifications

• Intake Runner Volume: 229cc
• Exhaust Runner Volume: 97cc
• Combustion Chamber Volume: 62cc
• Valve Angle: 15°
• Intake Valve: 2.02-inch stainless steel
• Exhaust Valve: 1.57-inch stainless steel
• Valve Guides: Bronze
• Valve Springs: PAC dual springs
• Retainers: Titanium
• Valve Seals: Viton
• Spring Seats: 1.250-inch steel
• Casting: 4-bolt LS cathedral-port
• Minimum Engine Bore: 3.780 inches
• Minimum Head Gasket Bore: 4.030 inches
• Flat milling rate: Approximately 0.007 inch per cc.
• Optional chamber softening available.
• Complimentary chamber milling available upon request.

Notes

• Designed specifically for 4.8L and 5.3L LS engines but compatible with all larger cathedral-port LS engines.
• Small-bore chamber design clears every LS bore from 3.780 inches (4.8L) and larger.
• Maintains OEM LS valve angle and valve spacing for stock-geometry compatibility.
• Ideal for naturally aspirated and forced induction combinations.
• Engineered and CNC machined in-house in small production batches for maximum consistency.