By Marine One Motorsports – Lake Havasu City, AZ When it comes to pushing your personal watercraft (PWC) to the next level, few upgrades make a bigger impact than ECU tuning . Whether you’re racing across the lake, chasing smoother throttle response, or just want a more responsive ride, ECU tuning can completely transform your machine’s performance. What is ECU Tuning? Every modern PWC is controlled by an Engine Control Unit (ECU)  — the onboard computer that manages fuel del