Description
EnginePlease call if looking for this part ASAP as the website inventory may not be accurate during peak season.
Features:
- Designed for 2019+ Patriot 850 and the new 9R engines
- Increase cooling capacity for lower running temps which helps maintain peak power
- Low altitude kits gain 4-5 mid-range and peak horsepower
- High altitude kits gain 8-9 HP in the mid-range and 7-8 peak
Additional Info:
- SKU - 04-318
- No tune is required when running just the head on the 850, but it is recommended for maximum gains.
- Tune is required for use with the 9R.
- BMP tune is required when running in combination with a BMP pipe.
- We recommend running BPR9ES NGK plugs.
- Pump gas 91 is required.
Dome Configurations:
850-36.5cc is a 12.5:1 compression ratio that works great in the 6,000-9,000 ft range and bolts on 7-8 HP in the mid-range and 5-6 HP peak.
850-40.5cc is the lower 11.8:1 compression version for sea level to 6,000 ft and gains 4-5 HP. The stock 12.1-12.2:1 compression ratio makes the motor's detonation sensor kick on very easily and won’t allow you to lean out the motor for extra power. By bolting on this version it allows you to lean out your machine with a fuel controller and pick up 5-6 safe horsepower. Some people have purchased this version simply to make it run cooler and less likely to set off the detonation sensor and put the sled in limp mode. This dome design is different than others with a unique wider squish band and radius giving you great power and better reliability.
- High altitude 850 PN: 04-318-H
- Low altitude 850 PN: 04-318-L
- High altitude 9R PN: 04-318-H-900
- Low altitude 9R PN: 04-318-L-900