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How much does an intercooler matter on a 7.3 Power Stroke? Let's let the dyno settle this debate.

The 7.3 Power Stroke is a workhorse, but let’s be honest: by today's standards, the factory power output of those classic Old Body Style (OBS) and E-Series trucks leaves a lot to be desired. While a stock OBS 7.3 might have rolled off the line making anywhere from 215 to 250 horsepower, today’s modern diesel trucks are pushing 425 to over 500 horsepower right off the showroom floor.

Want your classic Ford to keep up with modern traffic and tow heavy without breaking a sweat? You need upgrades. But here's the million-dollar question: How much power are you actually losing by running a non-intercooled setup on your OBS 7.3 Power Stroke? We decided to skip the sales pitch, strap one of our engines to the dyno at Choate Engineering Performance, and do some real-world A-to-B testing. Here is exactly what we found.

The Test Mule: The Choate 7.3 Workhorse Setup

To get accurate numbers, we used our in-house 7.3 Workhorse engine package. We wanted a setup that reflects what real diesel enthusiasts are building for daily driving and heavy towing. Our test engine was outfitted with:

• Stage 2 Gen 3 KC Turbo
• Adrenaline High-Pressure Oil Pump (HPOP)
• Custom Tuning
• 180/30 Single-Shot Injectors*

*These injectors are incredibly popular for tow rigs. The larger barrel paired with a 30-over nozzle allows the injector to unload fuel faster. This specific sizing is the sweet spot - go too large on the nozzle, and you lose the fuel pressure needed to properly atomize and incinerate the fuel. The 180/30 pairs perfectly with the Stage 2 turbo to keep your Exhaust Gas Temperatures (EGTs) in check while delivering massive torque.

The Results: Dyno-Proven Gains

After bringing the 7.3 up to operating temperature, we made our pulls. The difference between the non-intercooled and intercooled setup was staggering.

By changing absolutely nothing else except routing the intake through an intercooler, we gained 30 horsepower and 75 lb-ft of torque.

For this specific 7.3 Workhorse build, that brought the total consistent output to a highly respectable 425 horsepower and 950 lb-ft of torque.

The Science Behind The Power: Why The Intercooler Matters

Why does a simple intercooler swap yield such massive gains? It all comes down to mass air density.

When a turbocharger compresses air, that air gets incredibly hot. Hot air expands, meaning less oxygen per cubic inch. By passing that compressed air through an intercooler before it enters the intake manifold, we drastically cool it down, making it denser.

Denser air means more oxygen is crammed into the cylinders. More oxygen allows the engine to burn the fuel much more efficiently, resulting in:

• More Horsepower and Torque
• Lower Exhaust Gas Temperatures (EGTs)
• A Happier, Longer-Lasting Valvetrain

As any diesel veteran will tell you, supporting mods are where your primary upgrades truly shine. Pushing more fuel and air into an OBS Ford without an intercooler is a recipe for disaster. The upper portion of the engine takes a beating, and the exhaust valves can get dangerously hot, especially during heavy hauling up steep grades. Intercooling is the insurance policy that keeps your valvetrain alive while unlocking hidden power.

Ready To Upgrade? Start With A Solid Foundation

Whether you are doing an OBS 7.3 intercooler swap, upgrading your turbo, or chasing high horsepower numbers, your Power Stroke's bottom end needs to be able to handle the stress.

At Choate Engineering Performance, we specialize in solving the real problems found inside today’s most popular diesel powerplants, including the Ford Power Stroke, GM/Chevy Duramax, and Dodge Ram Cummins.

We don't just rebuild engines - we fully remanufacture and re-engineer them to outperform factory designs. A simple rebuild often reuses tired parts and skips critical precision machining. At Choate, every detail is inspected, machined, and upgraded to meet or exceed OEM specifications, correcting the known weak points of your factory engine.

In-House Machining and Engineering Excellence

Every Choate remanufactured diesel engine is designed and machined strictly in-house in the USA using advanced 4- and 5-axis CNC equipment, flow benches, and precision balancing technology. We eliminate OEM design flaws across all platforms - from the cracked pistons notorious in the Power Stroke 6.4L, to bearing failures in the Cummins 6.7L, and the broken crankshafts that plague the Duramax.

Take Your Build to the Next Level

Stop leaving horsepower, torque, and reliability on the table. If you want a truck that pulls like a freight train and lasts a lifetime, you need the right parts and the right foundation.

Shop online at Choate Engineering Performance today to find the perfect Short Block, Long Block, or Full Running Engine for your rig. Reach out to us if you have questions, and experience the strength of a true remanufactured diesel engine - because Stock Is Not An Option!