Fat Daddy Single Pipe and Y-Pipe // 2025-2026 Arctic Cat ZR / RIOT / M 858 C-TEC2 // 5000' + Elevation Only!

Speedwerx Fat Daddy Single Pipe and Y-Pipe // 2025-2026 Arctic Cat ZR / RIOT / M 858 C-TEC2 // 5000' + Elevation Only!

Our High Elevation Fat Daddy Pipe Kit for the Arctic Cat 858 adds 8 HP everywhere from 6000 RPM to 8300 RPM, and is 2.4 LBS lighter than stock too! The pipe and y-pipe both have a bright silver ceramic coating that not only looks good, but also helps with heat retention for more consistent runability. This pipe is designed and tested for use only at 5000’+ elevation with 91+ octane non-oxygenated pump fuel. It bolts right up using the stock hardware, and comes with a different graphoil donut for the exhaust outlet and a pipe banding kit for vibration dampening. It is compatible with the stock muffler or any of our Speedwerx mufflers, other mufflers have not been tested and are not recommended as different flow rates and back pressure may affect the runability and performance. Update 2/28: an ECU Tune is required with the Pipe/Head/Intake combo- see related products below.

• 8+ HP Gain
• 2.4 lbs Lighter Than Stock
• Fits Into Stock Muffler
• Ceramic Coated
• 100% Made In The USA!

Preliminary testing has shown a 18hp gain with our Pipe, Y-Pipe, Stealth Head, and Air Intake with at high elevation! We will be offering our Exterminator Kits for a complete package that include these parts plus an ECU Tune and Hypershift Clutch Kit for maximum power and performance in a bolt-on kit. Update 2/28: an ECU Tune is required with the Pipe/Head/Intake combo- see related products below.

TECH NOTE: Power Valve cables- we have seen a large number of sleds that the power valves are not set properly from the factory or they have moved, this dramatically effects the overall performance of you machine. Using AC tool # 836-00005 you need to confirm these are set right and if you have issues check them again. In our opinion, this is needed on every single 858 out there even in bone stock form. There is also a Technical Advisory regarding the Servomotor Bracket Alignment issued 12/5/25- your dealer may have already contacted you about this done this as part of the pre-delivery inspection, but they can help you with these adjustments if you are not comfortable doing them yourself. You can purchase the Adjustment Tool Kit here- https://speedwerx.com/apv-adjustment-tool-kit-858-c-tec2-models.html 

ABOUT OUR EXHAUSTS:
All of our Fat Daddy single pipes undergo countless hours of testing and development combined with hours of design and fitting. We have taken the time necessary to produce the best single pipes for your machines. Here are some of the key benefits to using our single pipes:

STRAIGHT-UP USA HORSEPOWER
Every pipe is designed, DYNO tested and then field tested to produce real, accurate and reliable horsepower gains. Our pipes are not built for one run across the lake or on the trail. Our pipes are built to last and our pipes work!

CERAMIC COATING
All of our single pipes come with a long lasting finish that offers a great look while also acting as a thermal barrier to keep heat inside the pipe for optimum performance.
 
LIGHTWEIGHT
All of our single pipes are lighter than the stock system.  You can expect an average weight savings of about 5 lbs.

GREAT FIT
All single pipes are designed to run into the stock muffler for simple installation.

QUIET
You can expect stock sound levels while using the stock muffler.