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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