2021-2026+ Ford Bronco 2.3L EcoBoost Custom Tune

Reasonable Basis - Emissions Testing Verified to have no adverse effect on emissions.

ZFG Racing LLC Reasonable Basis File Number: RBF-001

Products within this category, to the best of ZFG’s knowledge and understanding, demonstrate a reasonable basis that they do not adversely affect vehicle emissions and retain the full operation and functionality of the On-Board Diagnostic System (OBD) Emissions Related Items, and will continue to satisfy emissions requirements, such as meeting standards within useful life or maintaining emissions performance outside useful life. Such labeling does not indicate products are 50 state legal. Consumers are advised to make sure that such parts are installed and used properly in order to maintain compliance with emissions standards.

Reasonable Basis testing under the guidance of SMEA Garage Emissions Compliance for reasonable basis often coincides with CARB EO pending. Additional documentation available upon request.

 Tuning Package

• Includes RTD device + credits + custom tune

• Required for new customers

Tune Only

• For customers with a compatible HP Tuners device

• Device and credits not included

• Need credits? Purchase here.

Additional Tune

• For existing ZFG customers adding a fuel type or tuning goal

• Requires Tune Request submission

Looking for an MPVI? 

• Tune Only → MPVI + credits → at this link.

For more details on HP Tuners devices and licensing, please see our FAQ: Devices.

Each tune covers one fuel type:

• Auto-Octane — Flexible, adjusts to fuel (87–93 / e30)

• 91+ Octane — Balanced performance and flexibility

• 93+ Octane — Strong performance-focused option

• E50 — Maximum gains on stock fuel system (when available)

• E85 — Requires proper fuel system capacity

⚠️ See: Can I run an Ethanol Blend (E30 / E50 / E85)?

You can always restore the stock tune when running lower-octane fuel. 

 Standard Tune

• One custom calibration based on your selected goal

• Applies across all drive modes

💡 See: Can I still use the drive modes once tuned?

DMS™ (Drive Mode Specific)

• DMS™ Calibration is not supported for this platform

 • Submit a Tune Request after purchase (REQUIRED)

• Additional Tune is based on your existing file (no new files needed)

• You will receive instructions once your tune is ready

  ⚠️ See: Can I run an Ethanol Blend (E30 / E50 / E85)? 

✅ Best Practices:

• Flash First: Write your tune before blending

• Test: Measure ethanol content of both pump gas and E85

• Use the Ethanol Calculator 

• Wait: Drive a minimum of 15 miles, avoid going into boost

 Your tuning goal defines how the vehicle behaves:

• Tow — Optimized for low-end torque and towing

• Daily Driver — Balanced performance and drivability

• Performance — More aggressive power and shifting

• Race — Maximum performance, optimization of aftermarket modifications