Easy bolt on power for your 800 AXYS! This head has twice the cooling capacity to keep your motor running cooler to maintain horsepower by staying below the 120 degree timing curve.
We offer two different dome configurations:
800-37.5 is a 12.5:1 compression ratio that works great in the 6000-9000 ft range and bolts on 7-8 HP in the mid-range and 5-6 HP peak.
800-41 is our lower 11.8:1 compression version for sea level to 6000 ft and gains 4-5 HP. The stock 12.1-12.2:1 compression ratio makes the motors 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.
This head does not require a fuel controller when run by itself, or with our durability kit. If you run this head with our performance pipe, you will need a fuel controller.