Features

Lead Times Apply

• Hand-selected factory castings rigorously inspected for top quality.
• Riff Raff Stainless Injector Cups standard, eliminating brass cup failures.
• 100% Made in the USA from start to finish.
• Hardened high-nickel valve seat inserts and iron matrix valve guides for durability.
• 21-4N HD Stainless Nitrided Valves for superior longevity and wear resistance.
• HD Performance Springs with extra pressure for heavy towing, higher boost, and upgraded injectors.
• Precision CNC machining and in-house assembly ensure perfect fitment and reliability.
• O-ringed heads with Cometic MLX gaskets, permanently solving head gasket failures.
• No Core Charge, No Return Shipping.
• 12-month warranty against defects in materials and workmanship.

Description:

Kill Devil Diesel’s 7.3 Powerstroke cylinder heads are built for maximum reliability, longevity, and performance. Every head is meticulously machined in-house on state-of-the-art CNC equipment, hand-assembled, and rigorously inspected to exceed OEM durability.

KDD starts with only the best factory Ford castings, which undergo a multi-step inspection process, including chemical cleaning (to prevent abrasive contamination), magnaflux crack detection, and pressure testing. Once qualified, each head is:

• Machined for hardened high-nickel valve seats (solving factory wear and cracking issues).
• Resurfaced on a precision RMC V40 CNC machine for a perfect finish.
• O-ringed and paired with Cometic MLX gaskets—a proven solution for preventing head gasket failures.
• Equipped with our proprietary Serdi-machined valve seat profile for optimized airflow and durability.
• Assembled with USA-made stainless nitrided valves, Riff Raff stainless injector cups, and KDD HD Performance Springs—all rigorously tested to meet our exacting standards.

Every component is engineered to handle higher boost, extreme towing, and high-horsepower builds, ensuring your Powerstroke is built to last.

Key Components & Why KDD Chose Them

Valves – Stainless Nitrided for Extreme Durability

Unlike coated valves, nitriding is a permanent heat-treatment process that strengthens the stainless steel itself, improving hardness, temperature resistance, and reducing friction.  This results in:
✔ Lower friction → Cooler operation & reduced engine drag.
✔ Higher wear resistance → Ideal for heavy towing, turbo, supercharger, and nitrous applications.
✔ Made in the USA from 21-4N stainless steel from the hills of Pennsylvania, exclusively for KDD by an OEM valve supplier.

Valve Springs – Heavy-Duty Performance Springs

KDD’s proprietary HD valve springs offer superior durability over common aftermarket options (like the Comp 910). Designed for:
✔ Increased spring pressure → Supports higher boost & larger injectors.
✔ Micro-polished & heat-treated → Maximum fatigue resistance & longevity.
✔ Precision-checked in-house → Ensures perfect spring pressures for reliable performance.

Riff Raff Stainless Injector Cups – Eliminating a Common Weak Point

Stock brass injector cups are prone to cracking, corrosion, and fuel contamination. KDD equips every 7.3 Powerstroke head with Riff Raff stainless steel injector cups to:
✔ Prevent failures that cause coolant and fuel mixing.
✔ Withstand high temperatures & pressure without deforming.
✔ Ensure perfect fitment – CNC machined from USA-sourced steel in Washington State.

These upgrades set KDD 7.3 heads apart from the competition, providing unmatched reliability, strength, and performance.

📌 Please specify if you have an 8- or 10-bolt plenum in the order notes.
📌 No Core Charge, No Return Shipping.

This listing is for a pair of cylinder heads.  Contact our support team to ask about custom options such as CNC porting, coated combustion chambers, or custom spring options, etc.