When Stellantis introduced the 3.0L Hurricane twin turbo inline six, it marked a significant shift away from the HEMI V8. While both the Standard Output (SO) and High Output (HO) versions share the same engine architecture, they are designed with different performance goals in mind.

Although the engines appear nearly identical externally, there are several key differences that affect horsepower, torque, tuning potential, and aftermarket compatibility.

If you're shopping for performance parts, understanding these differences is critical.

Shared Engine Architecture

Both engines feature:

• 3.0L twin turbocharged inline six
• Aluminum block and cylinder head
• Dual overhead camshafts
• Direct fuel injection
• Electronic wastegates
• Variable valve timing
• Forged crankshaft
• Twin air to water intercooling system

The foundation of both engines is exceptionally strong, providing an excellent platform for performance modifications.

Power Comparison

The additional horsepower is not simply achieved through higher boost. The HO incorporates several hardware and calibration changes that allow it to produce significantly more power while maintaining factory durability.

Turbocharger Differences

One of the largest differences between the engines is the turbocharger package.

Standard Output

The SO utilizes smaller turbochargers designed to:

• Produce boost quickly
• Improve low RPM response
• Deliver strong everyday drivability
• Maximize efficiency

High Output

The HO receives larger turbochargers capable of:

• Higher airflow
• Increased boost capacity
• Greater horsepower potential
• Improved top end performance

These larger turbochargers require additional supporting hardware and engine calibration to safely produce their increased output.

Internal Engine Differences

The HO engine incorporates several upgraded components to withstand higher cylinder pressures.

These include changes to:

• Pistons
• Connecting rods
• Cooling strategy
• ECU calibration
• Fuel system calibration

While the overall engine design remains similar, these upgrades contribute to the HO's ability to reliably produce over 500 horsepower from the factory.

Exhaust Differences

Although both engines use twin turbochargers, the exhaust systems are not interchangeable.

The HO and SO downpipes utilize different:

• Turbo outlet geometry
• Mounting locations
• Pipe routing
• Oxygen sensor placement

Because of these differences, HO downpipes will not directly fit SO-equipped trucks, and vice versa.

Relentless Automotive Development has designed dedicated downpipe systems for each platform to ensure proper fitment while retaining OEM-style installation.

Fuel Requirements

SO

The Standard Output engine is designed to operate on regular gasoline, though premium fuel can improve performance under certain operating conditions.

HO

The High Output engine requires premium fuel to achieve its advertised horsepower and torque ratings.

Running lower octane fuel may cause the ECU to reduce ignition timing, resulting in lower performance.

Tuning Potential

Both engines respond well to aftermarket tuning.

Typical improvements include:

• Increased boost pressure
• Optimized ignition timing
• Improved throttle response
• Increased horsepower and torque

As with any forced induction engine, supporting modifications such as improved intake and exhaust flow can further enhance performance.

Which Engine Is Better?

The answer depends on your goals.

Choose the SO if you want:

• Excellent daily drivability
• Lower operating costs
• Strong low-end torque
• A solid foundation for mild performance upgrades

Choose the HO if you want:

• Maximum factory performance
• Greater aftermarket power potential
• Larger turbochargers
• Higher horsepower capability

Relentless Automotive Development HO and SO Downpipes

At Relentless Automotive Development, we developed dedicated downpipe systems for both Hurricane platforms rather than attempting to make one design fit both.

Each system is engineered specifically for its application and features:

• 304 stainless steel construction
• TIG welded assembly with back purging
• High flow GESI catalytic converters (optional)
• OEM mounting locations
• Precision fitment
• Ceramic coating available
• Designed and manufactured in the USA

This platform-specific approach ensures proper installation, optimal exhaust flow, and long-term reliability.

Frequently Asked Questions

Can HO downpipes fit an SO truck?

No. The turbo outlet geometry and overall downpipe design differ between the two engines, so dedicated downpipes are required for each platform.

Is the HO engine just an ECU tune?

No. While calibration is a major factor, the HO also includes hardware differences such as larger turbochargers and upgraded internal components.

Can the SO make HO power?

With the right combination of tuning and supporting modifications, the SO can produce substantially more power than stock. However, achieving HO-level performance reliably depends on the complete build and supporting hardware.

Which Hurricane engine has more aftermarket potential?

Both engines offer excellent potential. The HO starts with a higher performance baseline, while the SO provides a strong platform for enthusiasts looking to build power over time.

Final Thoughts

The Hurricane engine family has quickly established itself as one of the most capable turbocharged truck platforms available. Whether you own the Standard Output or High Output variant, understanding the mechanical differences helps you choose the right upgrades and avoid compatibility issues.

At Relentless Automotive Development, our focus is on designing platform-specific performance products that deliver measurable gains without compromising fitment or reliability.