Stage 1R – Ultimate Stock Muffler Package 250 HP on 91-Octane Pump Gas The Precision EFI Stage 1R was developed specifically for riders who want to keep the factory muffler while enjoying a substantial increase in performance. Designed for the Arctic Cat 9000 Series and Yamaha Sidewinder, this package delivers 250 horsepower on 91-octane pump gas while preserving the quiet operation and refined sound of the OEM exhaust system. If your goal is to build a fast, reliable trail sled without the added noise of an aftermarket exhaust, the Stage 1R is the perfect solution. Serious Performance. Factory Sound. By combining the Precision EFI High-Flow Air Intake with our proprietary ECU calibration, we've optimized airflow, boost pressure, ignition timing, and fuel delivery to safely extract 250 horsepower from the stock exhaust system. The result is a sled that feels dramatically different from stock: Instant throttle response Strong low-end torque Hard-hitting mid-range acceleration Smooth, linear power delivery Quiet, factory exhaust note It delivers the kind of performance most riders never expect from a sled equipped with the original muffler. Built for Trail Riders The Stage 1R was engineered with long-distance trail riding in mind. Unlike louder exhaust systems that can become tiring after a full day on the snow, the factory muffler maintains the quiet, comfortable ride you've always appreciated—while the Precision EFI calibration provides the performance you've always wanted. It's the ideal package for riders who spend hundreds of miles on the trail and want a sled that's fast without attracting unnecessary attention. Kit Includes Precision EFI Stage 1R ECU Reflash Precision EFI High-Flow Air Intake Recommended Upgrade We strongly recommend installing the Precision EFI Blow-Off Valve Kit. The factory blow-off valve has proven to be one of the weakest components on higher-boost applications. Upgrading it helps: Reduce compressor surge Improve turbocharger longevity Maintain consistent boost pressure Increase overall reliability Clutch Calibration Required To achieve the advertised performance, the Stage 1R requires adjustable primary clutch ramps (weights). Proper clutch calibration is essential to keep the engine operating at its optimum powerband. Target RPM: 9,000 RPM Refer to the clutch calibration recommendations included with your Precision EFI Stage package. Precision EFI Knock Protection Every Precision EFI ECU calibration retains the factory's sophisticated knock control strategy while optimizing engine performance. The Precision EFI Knock Protection System continuously monitors combustion conditions, allowing the ECU to react instantly when necessary to help protect your engine while maximizing performance. The Fastest Quiet Trail Package The Stage 1R has become the preferred choice for riders who want big performance without big noise. Delivering 250 horsepower on 91-octane pump gas, exceptional throttle response, and the reliability Precision EFI is known for, it's the perfect package for anyone who believes the fastest sled on the trail doesn't have to be the loudest.
