Description

Straightline Performance Arctic Cat Thundercat 9000 & Yamaha Sidewinder / SRX 998 Performance Header (2017–Current)

Massive 15 Horsepower Gain. Faster Turbo Spool. Premium Stainless Steel Construction.

Direct Bolt-On Performance Header

Retains All Factory Heat Shields

The Straightline Performance Performance Header is one of the most effective bolt-on horsepower upgrades available for the 2017-current Arctic Cat Thundercat 9000 and Yamaha Sidewinder / SRX 998 Turbo engines. Precision engineered to maximize exhaust flow, this premium full stainless steel header delivers a proven 15 horsepower gain, increased torque, and dramatically faster turbo spool while maintaining exceptional reliability.

Designed through extensive dyno development and real-world testing, the Straightline Performance Header improves exhaust scavenging and reduces restriction ahead of the turbocharger. The result is quicker boost response, harder acceleration, improved mid-range power, and stronger top-end performance.

One of the biggest advantages of the Straightline Performance Header is its OEM-style installation. The header is a direct bolt-on replacement that retains all factory heat shields, preserving the factory appearance while providing superior heat management and protecting surrounding engine components.

Constructed entirely from premium stainless steel, every header is precision TIG welded for maximum strength and durability. The corrosion-resistant stainless construction ensures years of dependable performance, even in the harshest snowmobile environments.

This header works exceptionally well on completely stock sleds but truly shines when combined with additional performance upgrades. It pairs perfectly with aftermarket ECU tunes, performance intakes, exhaust systems, clutch kits, and other horsepower modifications, making it one of the best foundation upgrades for any serious 998 build.

Although no additional modifications are required for installation, Straightline Performance highly recommends installing the proper clutch calibration to fully utilize the additional horsepower and torque produced by the header.

Whether you’re trail riding, lake racing, drag racing, or building a high-horsepower turbo machine, the Straightline Performance Performance Header provides substantial performance gains while maintaining factory fit and exceptional reliability.

Performance Benefits

• Proven 15 horsepower gain
• Increased engine torque
• Faster turbo spool
• Quicker throttle response
• Stronger mid-range acceleration
• Increased top-end power
• Improved exhaust flow
• Excellent foundation for future performance upgrades

Features & Benefits

• Fits 2017-current Arctic Cat Thundercat 9000
• Fits Yamaha Sidewinder and SRX 998 models
• Proven 15 HP increase
• Premium full stainless steel construction
• Precision TIG-welded assembly
• Faster turbo spool
• Increased torque throughout the powerband
• Improved throttle response
• High-flow exhaust design
• Retains all factory heat shields
• Outstanding fit and finish
• Direct bolt-on installation
• No cutting or fabrication required
• Excellent corrosion resistance
• Works exceptionally well with aftermarket ECU tunes
• Compatible with aftermarket intakes
• Compatible with performance exhaust systems
• Compatible with clutch kits and additional performance upgrades
• Designed and manufactured by Straightline Performance

Compatibility

Fits:

Arctic Cat

• 2017-Current Thundercat 9000

Yamaha

• Sidewinder 998 Turbo
• SRX 998 Turbo

Please verify your model and year before ordering.

Installation

• Direct bolt-on installation
• Uses factory mounting locations
• Retains all factory heat shields
• No cutting or modifications required
• Proper clutch calibration is highly recommended to maximize performance.
• Performs exceptionally well with aftermarket ECU tuning, intake systems, and additional engine modifications.

Kit Includes

• Straightline Performance Stainless Steel Performance Header
• Installation Instructions