Chevrolet C6 Corvette LS -LS3-LS7

Mangum Racing Brodix 267cc LS3 Cylinder Heads

Mangum Racing CNC Ported Brodix 15° LS3 Cylinder Heads

Built from Brodix 6-bolt LS3 castings with extra deck thickness, our Mangum Racing 15° LS3 heads are designed for serious naturally aspirated and boosted combinations that demand airflow, strength, and repeatability.

Each set is fully CNC ported in-house with brand new Centroid 5-axis CNC mills and Newen seat & guide machines. Every set of cylinder heads is hand blended and carefully inspected before final assembly to ensure dimensional accuracy and consistency.

Airflow Performance

(4.125” Bore Plate)

Intake (Radius Entry)

• .200” – 148 CFM
• .300” – 227 CFM
• .400” – 282 CFM
• .500” – 325 CFM
• .600” – 350 CFM
• .700” – 363 CFM

Exhaust (No Pipe)

• .200” – 114 CFM
• .300” – 164 CFM
• .400” – 200 CFM
• .500” – 233 CFM
• .600” – 240 CFM
• .700” – 243 CFM

With a 267cc CNC intake runner and optimized 96cc exhaust port, these heads deliver strong mid-lift numbers with excellent high-lift stability — making them ideal for aggressive hydraulic roller street & race builds needing to retain the stock valve locations & angles.

Premium Hardware & Construction

• 6-bolt Brodix LS3 casting with increased deck thickness
• 15° valve angle, OEM LS3 valve spacing
• 2.165” hollow stem stainless intake valves
• 1.600” hollow stem stainless exhaust valves
• Bronze guides
• PAC .660” dual spring package
• Titanium retainers
• Viton seals
• 1.250” steel spring seats
• 68.5cc CNC chambers (milling available at no charge)
• Chamber softening options for 4.000”, 4.065”, and 4.125” bore sizes
• .006” per cc flat milling available
• Minimum bore: 4.000”

Designed for Builders Who Care About the Details

These are not mass-produced heads. Each set is machined, assembled, hand blended, and inspected in small batches to maintain strict quality control and dimensional consistency.

Extra deck thickness adds durability for higher cylinder pressure combinations. The PAC .660” dual spring setup provides valvetrain stability for serious cam profiles. Stock pushrod length works in most applications but should always be verified based on camshaft and final milling.

If you’re building a combination needing to stay stock valve angles & locations then this cylinder head is hard to beat!

All Precision Race Components (PRC) cylinder heads come fully CNC-ported and machined using state-of-the-art technology!

Click Here to SEE why we build better heads!

MADE IN THE USA!!

CAST IN THE USA!!

MACHINED IN THE USA!!

PRC's aftermarket casting LS3/L92/L99 cylinder heads come standard with the following options:

• NEW PRC 13-Degree Valve Angle LS3 Castings
• Improved Piston-to-Valve Clearance For Extra Compression & Larger Camshafts
• Smaller Than Stock Intake Port Volume For Improved Port Velocity
• Manley Stainless 2.185" Intake, 1.60" Exhaust Valves
• Billet Rocker Pedestals
• TSP .660" Dual Spring Kit w/ PAC Valve Springs, Titanium Retainers, Seats, & Seals
• CHE Bronze Guides
• Completely Assembled and Milled to Your Specifications
• 60-68cc Chambers

All PRC cylinder heads are extensively researched and tested. The all-new PRC aftermarket casting LS3 cylinder heads are designed to flow considerably more than a gm ported casting while keeping the port sizes smaller for improved port velocity. The result is a cylinder head that is smaller than a stock GM LS3 port and moves more air than any other ls3 cylinder heads! 

The all new PRC aftermarket casting LS3 heads are the perfect option for customers looking for the ultimate in LS3/L99/L92 cylinder head technology

The PRC aftermarket casting LS3 cylinder heads are available in 2 different configurations: 

• 255cc Runners for max effort stock cube LS2/LS3/L99/L92 engines looking for a 370cfm cylinder head that can be aggressively milled & still keep better than stock p/v
• 260cc Runners For LS3/L99/L92 stroker engines needing a 380cfm+ cylinder head!

The 13-degree valve angle will allow for the ability to run more compression and larger camshafts thanks to additional piston-to-valve clearance!!  

With all PRC cylinder heads, quality and performance are our two highest priorities! In addition to performance, you will not find a better performing set of cylinder heads at this price (cost is for the pair!). Call one of our sales consultants today if you have any questions or if you would like to discuss your specific application.