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Borla XR-1 Multi-Core 3in Ctr-Ctr Oval 12in x 4.25in x 7.88in Rotary Engine Equipped Racing Muffler-Borla-BOR400372
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Borla XR-1 Multi-Core 3in Ctr-Ctr Oval 12in x 4.25in x 7.88in Rotary Engine Equipped Racing Muffler

Borla
BOR400372
808422003728
Muffler
20+ Units In Stock - Ships Next Business Day
$ 299.99 $ 267.99
FREE Ground Shipping!
$ 267.99

SKU: 400372   |   UPC: 808422003728

Borla 400372 XR-1 Multi-Core 3in Center Inlet/Outlet Oval Racing Muffler for Mazda RX-7 1986-2002 & RX-8 2004-2011 Rotary Engines

The Borla 400372 XR-1 Multi-Core muffler is a compact, high-flow racing component designed for rotary engine vehicles like Mazda RX-7 and RX-8. This universal part features a reversible design with 3-inch center inlet and outlet for easy installation and maximum exhaust flow. It delivers increased power, torque, sharper throttle response, and the signature Borla aggressive exhaust note.

Key Features

  • Patented Multi-Core Design: Enhances exhaust scavenging for better power output and refined sound control in high-horsepower rotary applications.
  • T-304 Stainless Steel Construction: Ensures lifelong durability with 100% welded build that resists corrosion and withstands extreme racing conditions.
  • Compact Oval Body: Measures 4.25in height x 7.88in width x 12in length (19in overall) to fit tight spaces on rotary-equipped vehicles.
  • Reversible Inlet/Outlet: Allows flexible orientation for custom exhaust setups on Mazda RX-7 FC/FD and RX-8 models.
  • High-Temp CRF Acoustic Core: Manages sound levels while maintaining unrestricted flow for track-proven performance.

Product Notes

  • Universal fit optimized for rotary engines; verify clearance before install.
  • No embossed logo for clean racing appearance.
  • Made in the USA with precision engineering for motorsport reliability.

Installation Notes

  • Professional installation recommended.
  • Clamp-on 3in pipe connections; use stainless hardware for longevity.
  • Reversible design supports left/right orientation; position for optimal ground clearance.

This Part Fits

Year Make Model Submodel
1986-1991 Mazda RX-7 FC (All)
1993-2002 Mazda RX-7 FD (All, incl. 13B-REW)
2004-2011 Mazda RX-8 (All, incl. 13B-MSP Renesis)

Why Choose Borla?

  • Decades of leadership in stainless steel exhaust for street and racing.
  • Proven gains in power, torque, and fuel efficiency across applications.
  • Million-mile warranty on materials and workmanship for peace of mind.

Frequently Asked Questions

  • Q: Will this muffler fit my Mazda RX-7 or RX-8?
    A: Yes, this universal XR-1 muffler is designed for 1986-2002 RX-7 FC/FD and 2004-2011 RX-8 rotary engines with 3in piping; reversible for custom routing.
  • Q: What material is the Borla 400372 made from?
    A: T-304 stainless steel with fully welded construction and high-temp fiber core for rust resistance and durability.
  • Q: Does Borla offer a warranty on this racing muffler?
    A: Backed by Borla's million-mile warranty against defects in materials and craftsmanship when properly installed.

Shipping & Handling

  • Method: UPS Ground or FedEx
  • Availability: In stock - ships same or next business day
  • Packaging: Securely boxed for protection
  • Weight: 8 lbs

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