Home / Snowmobile products / Yamaha / Precision EFI Yamaha Mountain Max 800 Stage1 +8hp Precision EFI Yamaha Mountain Max 800 Stage1 +8hp Yamaha Mountain Max 800 STAGE1 The Stage1 adds 8hp to your Yamaha Mountain Max without changing any parts! We have almost doubled the throttle response, you’ll be a lot faster than a stock one! Engine runs smoother and has more power & torque through all powerband. See the dyno chart on the left! For best performance with Stage1 we recommend DRT clutch kit! The Stage1 is available to be installed by any of our dealer, just bring your snowmobile or ecu and they will upgrade it Find your Precision EFI dealer here Categories: All Products, Precision Efi, Yamaha Description Reviews (0) Description Reviews There are no reviews yet. Be the first to review “Precision EFI Yamaha Mountain Max 800 Stage1 +8hp” Cancel replyYour rating * Rate… Perfect Good Average Not that bad Very poor Your review *Name * Email * Save my name, email, and website in this browser for the next time I comment.