Arctic Cat Unveils 858cc Twin, High-Tech Gauge For 2025

The large-displacement engine that Arctic Cat snowmobile fans were awaiting for the Catalyst chassis was unveiled today. The low-slung 858cc twin-cylinder two-stroke was shown at the massive Hay Day event in North Branch, Minnesota, on September 9.

     Cat officials say the new engine makes 11 percent more horsepower throughout its powerband than the 800 twin it replaces.

     Equally important, the Cat engineers stressed, the laydown architecture and the way it mounts in place is specifically designed for the Catalyst chassis. That will enable riders to take full advantage of the lightweight chassis and its centered masses that made first-year 2024 600-class Catalyst sleds so fun to test ride last spring.    

     The good news: The engine will be available in trail, crossover and mountain sleds in the Catalyst chassis. And the bad? You’ll have to wait until model year 2025 machines to experience it.

     Arctic Cat also unveiled a new high-tech gauge that’ll be available on 2025 models. Dubbed the Arctic Cat G8 Powered by Garmin, it features the sort of on-screen mapping, phone connectivity, group ride capabilities and more that have been available from competitive brands in recent years but not Arctic Cat.

The New Arctic Cat Engine

Cat made a monstrous splash at the 2022 Hay Days event when it unveiled its long awaited new chassis platform. The Catalyst has been a huge attraction, but the 600-class powerplant it was unveiled with was a bit of a disappointment to many. Right at the chassis’ release, though, Cat officials pledged publicly that a larger displacement two-stroke was in development.

     Now unveiled, it uses the same 85mm cylinder bore but a longer, 75.6mm stroke than the engine it replaces. That allows it to reach its 858cc displacement.

     Like the 600 and other modern Arctic Cat two-strokes, it features a lay-down design with both intake and exhaust pointed toward the driver/center of the chassis. Cat engineers have long said this design allows the brand to better center masses in a chassis.

     This new 858, though, also mounts 3/8 of an inch lower in the chassis than the 600. The key is a new crankcase with integrated engine mounts. The reed cage was also moved 12mm closer to the cylinders. That improves airflow while also allowing room for the centerline steering system that is one key to the Catalyst design.

     Also unique is a new variable exhaust system with a push-pull actuator that is controlled by a servo that gets its directions from the sled’s ECM. That allowed it to be fully tunable for both performance and emissions, according to Troy Halvorson, Arctic Cat’s director of snowmobile product strategy.  He said it provides 250 percent more exhaust port height change than the previous design, allowing it to be nice and tight on the bottom end yet very free flowing on top-end.

     The system is also light, he stressed. With the previous design, there are about 30 parts per cylinder in the exhaust valve system. That’s been cut in half.

     Stripping weight while maintaining durability continued to be a focus of everything tied to the Catalysts. This new 858 twin, Cat officials said, is about 4 percent lighter than the engine it replaces. It’s also lighter than the 600 twin already in the 2024 Catalysts. Weight was also taken out of the exhaust system.

     Cat officials wouldn’t release a horsepower number on the engine in discussions with the snowmobile media. Instead, they went back to their pledge of an 11 percent increase. That 11 percent is found throughout the powerband, they said.

The New Arctic Cat Gauge

The Arctic Cat G8 Powered by Garmin will get the brand right in the middle of the action when it comes to high-tech touch-screen displays, connectivity and usefulness. It’s an increasing customer demand.

    “This has been something that we’ve been striving to get,” Halvorson said. “We wanted to work with Garmin because they are a very reputable brand and are one of the top companies with it comes to GPS technology.”

     The gauge works specifically with Arctic Cat’s CAN bus (Controller Area Network) system, Halvorson said, to give riders information on the snowmobile at a glance. Beyond that, on-screen trail maps, route planning and cell phone connectivity are included.

     You can also do group rides that track up to 20 riders in your crew, and connect via radio communication, Bluetooth and/or cellular connections.  

Arctic Cat Talking Points

Below are the official talking points Cat officials released on their new engine. Everything from here down is straight from Cat:

Purpose-Built for the Catalyst Platform

• The 858 engine was designed to optimize the Catalyst platform’s centralized design, so the rider is the active force providing more power with more precision and control.

• The innovative laydown engine design places the intake and exhaust in front of the engine allowing for the industry’s best mass centralization and lower center of gravity that the rider can feel for incomparable maneuverability.

• Improved exhaust valve and fuel system controls for increased performance and reduced emissions.

• The design is based on decades of Arctic Cat innovation complemented by the ingenuity of the current team to ensure the engine components fit the Catalyst platform’s design. From working around the centerline steering to integrating components for weight reduction and increased performance, there were no compromises in building an engine that would take the Arctic Cat ride experience to the next level.

• When designing Catalyst, Arctic Cat considered the different powerplants that would be housed in the platform. The brand-new 858 engine is an even lighter package with a lower center of gravity creating a better power to weight ratio for a unique ride.
• Available across trail, crossover and mountain platforms.

Optimized Power in the Industry’s Easiest to Ride Package

• Along with its innovative design to complement the Catalyst platform’s mass centralization, the 858 engine provides the right amount of horsepower for superior performance.

• A new air intake system that is integrated into the platform maximizes airflow to the engine for more power output. Multiple secondary, under-hood inlets prevent snow ingestion and optimize performance in all snow conditions.

• The new, patented exhaust valve design is the latest, most advanced in the industry. It stays tight to the piston as it moves and provides smoother exhaust port flow throughout a wider RPM range on both primary and auxiliary ports. It also provides seamless power and cleaner emissions.

• Compared to Arctic Cat’s 800 engine, the 858 engine provides 11% more power and torque, providing quicker acceleration and a high top speed.

More Power with Lighter Weight for an Exhilarating Ride

• With its integrated engine mounting design and new exhaust system, the 858 engine is 4% lighter in weight than the current 800engine. It’s also lighter and provides a lower center of gravity compared to competitive engines.

• A lighter weight design coupled with the Catalyst platform’s centralized mass and low center of gravity provides easier and more-precise handling for a ride experience like no other.

• To keep a lightweight, compact size for the Catalyst platform, Arctic Cat used an 85mm bore while increasing to a 75.6 stroke to achieve more horsepower and deep, bottomless torque that pulls hard and smoothly through the entire RPM range. The result is a power-dense, easier to ride package.

• The 858’s power-to-weight ratio coupled with the unique, lightweight Catalyst platform design takes carving through deep snow, maneuvering tight trails and boondocking to the next level.

Durable and Reliable to Spend More Time on the Snow

• The Catalyst platform was designed to be durable and easy to service with its belt drive system and completely tool-less plastic panels that are removeable for access to critical components. The 858 engine was built to complement the platform. The result: a snowmobile that can withstand the rigors of riding and minimize time off snow.

• Arctic Cat took learnings from the time-tested 400 and 800 engines and created the incredibly durable and reliable 858 engine.

• The engine has fewer parts and integrated mounting design in the crankcase — making it strong and easy to service.

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