Description

The HKS Mastery ECU Phase 1 is the foundational engine management upgrade for the GR Corolla, focused on enhancing drivability and unlocking performance potential. This professional mail-in reflash service removes the restrictive 180 km/h speed limiter and provides optimized base calibrations that improve throttle response and engine smoothness. While not targeting peak power gains, Phase 1 prepares the ECU for future modifications and works in perfect synergy with the HKS Power Editor, creating a powerful and reliable tuning platform.

Product Overview & Purpose

This is a mail-in ECU reprogramming service where HKS specialists overwrite your factory ECU with their proprietary Phase 1 calibration. The primary function is to eliminate the factory speed governor, allowing the vehicle to reach its natural top speed—essential for circuit use. Additionally, it refines the base engine maps to improve driveability and serves as the required electronic foundation for safe and effective use with bolt-on tuning devices like the HKS Power Editor.

Product Highlights

🚫 Removes 180 km/h Speed Limiter
The core feature of Phase 1 is the permanent removal of the factory 180 km/h (112 mph) speed governor. This is a critical modification for track days, high-speed driving, or regions without such restrictions, allowing the GR Corolla to perform to its full aerodynamic and gearing potential.

⚙️ Optimized Base Calibration for Enhanced Drivability
While not focused on peak horsepower, HKS engineers refine the factory calibration. This can result in smoother throttle response, improved part-throttle behavior, and a more linear power delivery, enhancing the overall driving feel and providing a more polished base for further tuning.

🔌 Perfect Synergy with HKS Power Editor
Phase 1 is specifically designed to be the ideal partner for the HKS Power Editor (42018-AT021). The reflashed ECU provides a more responsive and stable platform, allowing the Power Editor to manage increased boost more effectively and safely, resulting in a “pleasant ride” with significant power gains when used together.

🛡️ HKS-Engineered Reliability & Compatibility
All calibrations are developed and tested by HKS on actual GR Corollas (including the Morizo Edition), ensuring safety, reliability, and compatibility with factory and HKS parts. It maintains all OEM diagnostics and safety protocols.

Technical Specifications & Process

• Product Name: Mastery ECU Phase 1

• Model Code: 42019-AT011

• Compatibility: Toyota GR Corolla (GZEA14H, G16E-GTS, December 2022 – February 2025 production). Compatible with Morizo Edition and post-March 2025 models.

• Service Type: Mail-in ECU reprogramming.

• Key Feature: Speed limiter removal (180 km/h → 300 km/h).

• Turnaround: ECU is typically returned within 3 business days of receipt at HKS.

• Performance: Focus on drivability refinements; does not target peak power increases.

Performance Philosophy

• Goal: To provide the essential first step in electronic tuning by removing artificial performance limits and creating a superior, more responsive base calibration. The focus is on enabling future performance, improving driveability, and ensuring safe integration with supporting hardware.

• Focus: The mandatory first step for the tuning-minded owner. It is the perfect choice for those planning to use a Power Editor, for track enthusiasts who need the speed limiter removed, or for any owner seeking a more refined and direct driving experience from their stock or lightly modified GR Corolla.

Service & Usage Notes

• 📮 Mail-In Service Process
  This is not a DIY product. You must remove and ship your ECU to an authorized HKS service center. Vehicle downtime is typically 3-5 business days plus shipping.

• ⚠️ Important Considerations

  • Synergy with Power Editor: For significant power gains, pairing with an HKS Power Editor is highly recommended, as Phase 1 alone does not increase peak output.

  • Foundation for Mods: Serves as the optimal base calibration for vehicles with or planning to install intake, exhaust, or intercooler upgrades.

  • Warranty: As with any ECU modification, this may affect the vehicle manufacturer’s powertrain warranty.

■Test vehicle information