Vance & Hines V66043 Fuelpak FP4 Harley-Davidson Softail/Touring 21-23. From the Vance & Hines team who created the Fuelpak FP3 the worlds best-selling ECU tuner for Harley-Davidson motorcycles. Vance & Hines FP4 is the most intuitive tool on the market giving you the ability to control motorcycle tuning view live sensor data all using your smartphone. The Vance & Hines FP4 brings legendary tuning fuel trim and performance to the 2021-2023 Harley-Davidson Touring and Softail models with all the new features and ease of use you expect. The Vance & Hines FP4 brings our legendary fuel tuning and performance to your 2021-2023 Harley-Davidson motorcycles, with all new features, and the ease of use you expect from Vance & Hines.
With its state-of-the-art Bluetooth enabled app-driven technology, FP4 empowers you to do 100% of your tuning right from the palm of your hand with your mobile device, backed by industry-leading customer support, all while maintaining 49-state emissions compliance and thereby keeping your Harley-Davidson factory warranty intact.