Description
The Borla XR-1 Multi-Core Racing Muffler (Part Number 400371) is engineered specifically for rotary engine equipped vehicles, offering exceptional performance and durability. Its compact size makes it an ideal choice for applications with limited space, while the reversible design provides installation flexibility to suit various configurations. Crafted from premium T-304 stainless steel, this muffler guarantees corrosion resistance and long-lasting strength, complemented by 100% welded construction that enhances durability under demanding conditions. The patented Multicore design maximizes exhaust flow, delivering increased power suitable for high horsepower applications. The high-temperature continuous-filament fiber acoustic material effectively reduces noise levels without compromising performance, ensuring a refined sound profile. Made in the USA, this muffler embodies quality and craftsmanship from the industry’s most experienced exhaust brand. Its oval body measures approximately 4.25 inches by 7.88 inches with a length of 16 inches, and overall length of 21 inches, making it a versatile and universal fit for a range of vehicles needing high-performance exhaust solutions. Whether upgrading a rotary engine or enhancing an existing system, the Borla XR-1 muffler delivers maximum power, durability, and sound control for motorsport enthusiasts and professional racers alike.
Features:
- Designed for rotary engine equipped vehicles but suitable for other applications
- Compact size ideal for limited space installations
- Reversible design for flexible installation options
- Patented Multicore technology for maximum exhaust flow and power
- Constructed from corrosion-resistant T-304 stainless steel
- 100% welded for enhanced strength and durability
- High-temperature continuous-filament fiber acoustic material for sound control
- Made in the USA for quality assurance

























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