12:1 Compression Ratio: Standard setup optimized for pump gas

Polaris RZR 4

The slip-on muffler allows for the use of two stock spark arrestors

200g Red Scale (Premium): Features a 200g capacity and includes a calibration weight to ensure your measurements remain 100% accurate over time

Summit models can quickly adjust for low & high RPM without removing the ramps

Helix / Ski-Doo Select Helix Angle:XP4 (850 High Elevation) 12:1 Compression Ratio: Standard setupHigh quality progressive angle helixes for the Ski Doo QRS secondary clutch. XP1 800 XP2 850 NA (Low Elevation) XP3 600 (High Elevation) XP4 (Steep N Deep) 850 NA XP5 850 Turbo