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New 6CT 8.3L 12V Cummins Cylinder Head – Precision Engineered with 21" Air Intake

New 6CT 8.3L 12V Cummins Cylinder Head – Precision Engineered with 21″ Air Intake

$1,225.00

2-Year
Warranty
Unlimited Mileage
Assembled
In USA
Florida-Based Shop
Quality
Tested
Pressure & Vacuum
Flat Rate
$65 Ship
No Surprises
5 sold

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No Core Charge Required Up Front Return your old head after you receive yours — we send a prepaid label

Please verify that your application requires the 21-inch air intake opening rather than the standard 16-inch version. Includes valves and springs.

New 6CT 8.3L 12V Cummins Cylinder Head – Precision Engineered with 21" Air Intake 📊

Upgrade your Cummins engine with this precision-engineered 8.3L 12V cylinder head, specifically designed with a 21" air intake for maximum volumetric efficiency.

This is a brand-new, high-strength cylinder head for the Cummins 6CT 8.3L 12V engine. Stand out from standard models with its larger 21" air intake opening—a crucial upgrade over the common 16" version—designed to optimize airflow, improve combustion efficiency, and unlock peak power output for heavy-duty applications.

🛠️ In-House Machining Process

  • Debris-Free Preparation: Every new casting is chemically cleaned and blown out to remove all residual machining oils and manufacturing debris. This ensures your heavy-duty engine's oiling system remains uncontaminated from start-up.
  • In-House Precision Machining: Unlike "shelf-stock" heads, we perform all final machine work in-house. This includes final guide sizing and precision valve seat cutting to ensure perfect geometry and clearances before reaching the assembly bench.
  • Pressure & Integrity Testing: To go beyond the factory standard, we pressure-test every head to 60 PSI. This verifies that the casting is free of porosity leaks or internal defects that could compromise performance in high-stress industrial environments.
  • Dimensional Inspection: Our technicians perform a multi-point inspection of the gasket-sealing surface and bore alignment. This ensures the head is perfectly flat and meets tight OEM tolerances for a flawless fit.
  • Professional Assembly & Setup: Valvetrain components are installed and verified in a clean-room environment. We check spring heights and seal seating to ensure the assembly is balanced and ready for the demands of construction and agricultural use.
  • Vacuum-Seal Verification: Every intake and exhaust port is Vacuum Tested. This guarantees a 100% airtight seal between the valves and seats, ensuring maximum compression and peak performance right out of the box.

📊 Technical Specifications

  • Condition: Brand New Heavy-Duty Casting
  • Engine Compatibility: Cummins 6CT 8.3L (12-Valve)
  • Air Intake Size: 21" Opening (Enhanced airflow vs. standard 16")
  • Material: High-Quality Robust Alloy for exceptional wear resistance
  • Performance Focus: Improved combustion efficiency and reduced fuel consumption
  • Assembly Status: Fully Loaded with valves and springs
  • Core Return: No Core Return Required
  • Application: Heavy-Duty Trucks, Agricultural, Construction, and Industrial Engines

🚘 Common Applications

Built for the most challenging jobs and industrial environments:

  • Heavy-Duty Trucks: Long-haul and regional transport units
  • Agricultural Equipment: Tractors and harvesters using 6CT powerplants
  • Construction Machinery: Excavators, loaders, and stationary equipment
  • Industrial Engines: Power generators and high-torque pumping units

📦 No Core Return & Warranty

  • No Core Return Required: This is a brand-new cylinder head — keep your old core. No upfront core fee, no return shipment, and nothing to send back.
  • Warranty: Includes a 2-Year Unlimited Mileage Warranty covering defects in materials and workmanship. Click here for Warranty details.

Please Note: Parts, marine, and performance items carry specific warranty limitations — please review our full Warranty Policy for details.

★★★★★
Verified Google Reviews
★★★★★

Part came in and work as a champ. Price was better than all other places I look for the set. Will recommended to all my soldiers and/or buddies if they need cylinder heads replace. Thank you guys.

— Demian Mingo
★★★★★

They supplied me with a perfect set of heads to bring my 1999 Ford Ranger back to life. Ranger Frank has been in the family since the day he rolled off the showroom floor. Its great to have him back on the road.

— Ron Long
★★★★★

Best prices and customer service on Duramax LML heads out there. Shipped fast and very cool about how long it took to get the cores back.

— Dan
★★★★★

I got my cylinder head quicker than expected. I would buy from this company again

— Devin Ciccarello

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6ct cylinder head 8.3l
New 6CT 8.3L 12V Cummins Cylinder Head – Precision Engineered with 21" Air Intake$1,225.00
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