Arctic Cat unveils big 858cc engine, Garmin gauge for 2025

With Hay Days in the review, we would be remiss if we didn’t mention the new 858cc Arctic Cat engine that was first shown to the snowmobile media at its factory in St. Cloud, Minnesota, where it will be built.

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

The new 858cc twin keeps Cat’s laydown design, with intake and exhaust on the same side of the engine. (Photos: Snow Goer)

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.

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.

Top cutaway view of the new 858cc Cat engine.

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, which is one key to the Catalyst design.


Arctic Cat reeds

The new Arctic Cat 858 engine will utilize VForce reeds that will mount closer to the cylinders for better airflow and also due to space constraints.

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 the top end.

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.

Updated Garmin touch-screen

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 new Arctic Cat G8 Powered By Garmin gauge will be available on select model year 2025 machines, but it will be able to be retrofitted to earlier Catalyst models.

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.

Read the full scoop on Snow Goer’s website.