Vance & Hines 66155 FuelPak FP4 ECU Tuner Fuel Management System

The Vance & Hines FuelPak FP4 (PN 66155) is a Bluetooth-enabled ECU flash tuning module designed for Harley-Davidson motorcycles. Building on the legacy of the best-selling FP3, the FP4 delivers a more intuitive, app-driven tuning experience that lets you manage every aspect of your motorcycle's fuel calibration directly from your smartphone.

The FP4 connects wirelessly via Bluetooth to any compatible iOS or Android device and uses Flash technology to recalibrate engine parameters, optimizing fuel delivery for performance exhaust systems, air cleaners, and other Stage 1 upgrades. Maps are developed in-house by Vance & Hines calibration engineers on a dynamometer and verified on the road, covering a wide range of exhaust and intake combinations.

Key Features:

• Bluetooth Flash Tuning – Recalibrates the ECM wirelessly via the free FP4 smartphone app (iOS and Android)
• Autotune – Tunes while you ride using data from the stock O2 sensors; flash collected data back to the ECM after your ride
• Expansive Map Library – Access thousands of dyno-tuned calibrations for virtually all combinations of Vance & Hines and other brand exhaust and intake systems
• Live Sensor Data – View real-time speed, RPM, cylinder head temperature, voltage, gear selection, and more from the app
• Advanced ECU Table Access – Adjust idle RPM, rev limiter, VE tables, target air-fuel ratio, and spark advance directly in the app
• Performance Data Logger – Record your ride and analyze all available sensor data along a mapped route
• OEM Calibration Backup – The factory fuel map is stored in the FP4, allowing the ECU to be returned to OEM settings at any time
• Simplified LED Indicators – Streamlined status LEDs keep you informed of connection and tuning status at a glance
• Compact & Durable – Made from polycarbonate plastic; smaller and thinner than the FP3 for a low-profile installation
• 49-State Emissions Compliant – Maintains Harley-Davidson factory warranty when used as directed
• 1-Year Warranty – Backed by Vance & Hines' extensive one-year warranty

Important Notes: Once the FP4 is used to flash a motorcycle, it permanently marries to that bike's VIN and cannot be used to tune a different motorcycle. The FP4 can still be used on other bikes for reading/clearing trouble codes and viewing live sensor data. Not legal for sale or use in California on pollution-controlled motor vehicles.