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The 7.3L Powerstroke is widely regarded as one of the most reliable diesel engines ever built. But when it comes to pushing horsepower, improving combustion efficiency, or simply ensuring your build can survive high EGTs and aggressive tuning, stock pistons aren't enough.

That's where Coated, Flycut, and Delipped Pistons come in.

These aren't just buzzwords used by performance builders -- they're critical upgrades that solve real-world weaknesses in the 7.3's internal design. In this article, we'll break down what these piston mods are, why they matter, and how they enhance both performance and longevity in your diesel build.

What's Wrong with Stock 7.3 Powerstroke Pistons?

Stock 7.3 pistons are cast aluminum units designed for reliability in stock conditions. But they weren't build for high RPMs, added boost, long-duration towing, or performance tuning. The factory design includes:

• A deep combustion bowl (lip) that increases heat concentration
• No valve reliefs (flycuts) for bigger cam profiles
• No coatings to protect from high heat and friction

When pushed hard, these pistons can suffer from:

• Cracking at the bowl edge (lip)
• Thermal fatigue from high EGTs
• Piston melting from prolonged heat soak
• Interference with larger valves or performance cams

Delipped Pistons - Reducing Heat Stress and Cracking

What is "Delipping"?

Delipping involves machining off the sharp outer lip of the piston bowl. This lip is a common failure point because it's thin, sharp, and takes the brunt of heat and pressure during combustion -- especially when tuning or running high EGTs. Delipped pistons are best for tuned 7.3s, towing builds, and high EGT environments. You can check out our delipping services here.

Why It Matters for the 7.3:

• Eliminates stress risers that lead to piston cracking
• Reduces thermal fatigue in the bowl area
• Helps the piston survive under sustained high loads or racing conditions

Flycut Pistons - Cam and Valve Clearance

What is Flycutting?

Flycutting involves cutting reliefs or pockets into the piston crown to give extra clearance for intake and exhaust valves -- especially helpful when running a performance cam with higher lift and longer duration. Flycut Pistons are best for performance builds with aftermarket camshafts or ported heads. You can check out our flycutting services here.

Why It Matters:

• Prevents valve-to-piston contact in high-lift camshaft applications
• Essential when increasing RPM range or using oversized valves
• Enables more aggressive valve timing and breathing

Coated Pistons - Thermal and Friction Protection

What Are Coated Pistons?

Coated pistons use advanced materials applied to the piston surfaces to reflect heat away from the piston crown (ceramic coating) and reduce friction between piston skirts an cylinder walls (graphite or moly coating). Coated Pistons are best for all builds -- especially tuned, high EGT, or towing applications. You can check out our coating services here.

Types of Coatings:

• Crown Coating (usually ceramic): Resists combustion heat, helps prevent melting or distortion
• Skirt Coating (usually film lubricant): Reduces wear, noise, and friction

Benefits in the 7.3:

• Improves piston lifespan under extreme heat
• Prevents scuffing and wear during cold starts or heavy loads
• Reduces oil consumption and blow-by

Combine All Three for a Bulletproof 7.3 Build

Here at Choate Engineering Performance, we offer pistons that are coated, flycut, and delipped -- making them ideal for high-horsepower and heavy-duty applications. It's the ultimate setup for diesel longevity, power, and peace of mind.

Why This Combo Works:

• Coating protects against the heat and friction of real-world driving and tuning
• Flycuts allow for custom cams and improved breathing
• Delipping prevents cracking under high boost

Pro Tip: Don't Upgrade Pistons Without Matching Components

When installing upgraded pistons, consider pairing them with:

• Gator Head Studs to keep combustion sealed
• Performance Camshaft to take full advantage of flycut pistons
• Balanced Rotating Assembly to reduce vibration and wear at high RPM
• High-flow injectors and Upgraded turbo to make use of stronger piston designs

Recommended by Choate

Choate Engineering Performance offers Coated, Flycut, and Delipped Pistons for the 7.3 Powerstroke as a Set. Already have your pistons? No problem. We can coat, flycut, and delip your pistons for you. And if you're looking for a full build, we offer these pistons in all of our Workhorse builds for our 7.3 engines.

Final Thoughts: Don't Skip Piston Upgrades in Your 7.3 Build

If you're investing in a 7.3 Powerstroke engine rebuild, piston upgrades are non-negotiable. Stock pistons were never meant to handle 500+ horsepower or 1,200 degrees farenheit EGTs. By upgrading to Coated, Flycut, and Delipped Pistons, you protect your investment and unleash the full potential of your diesel build.

Whether you're towing across the country or racing down the strip, these piston mods ensure your 7.3 runs stronger, cooler, and longer.