9R Stage 4 Kit 850engperform The stock ECU is designed

The stock ECU is designed to lessen oiling as air thins out (you rise in elevation and theoretically load drops)

OEM 9R cylinder

2023+ Skidoo Gen 5 146 Free Ride

2024    850 INDY XC 137

9R Stage 4 Kit 850engperform The stock ECU is designed9R Stage 4 Kit Big NA power. This is the full send Stage 4 package for riders who want a nasty pull, crisp throttle response, and a tune built for how you ride. 200 HP on 91 octane 210 HP on C14 race fuel Included Full port & polish Head Pipe modifications Custom clutching (matched to your weight & elevation) ECU flash (Customer can also flash their own ECU if they have or purchase a flash device) Gaskets You Ship Cylinders Exhaust valves Stock pipe