SKU: 400373 | UPC: 808422003735
Borla XR-1 Multi-Core 3in Ctr-Ctr Round 16in x 6.25in Rotary Engine Racing Muffler 400373 Fits Mazda RX-7 RX-8
The Borla 400373 XR-1 Multicore Muffler delivers aggressive racing sound and performance gains for rotary engine vehicles like Mazda RX-7 (1979-2002) and RX-8 (2004-2011). This universal 3-inch center inlet/center outlet design with 16-inch long 6.25-inch round body suits high-horsepower rotary setups and trucks. Gain power, torque, better fuel economy, and durable T-304 stainless construction for track or street.
Key Features
- Patented Multicore Design: Increases exhaust flow for maximum power in rotary and high-horsepower applications.
- T-304 Stainless Steel: Rust-proof material with 100% welded build ensures lifelong strength and heat resistance.
- Reversible Ends: Center-to-center 3in pipes allow easy adaptation for custom or truck installs.
- CFF Acoustic Core: High-temperature fiber controls deep Borla racing tone without restriction.
- 21in Overall Length: Long body fits rotary engines perfectly, extends to other uses with flexibility.
Product Notes
- Ideal for Mazda rotary engines; adaptable to other vehicles with 3in piping.
- No embossed logo for clean racing appearance.
- Ships ready for off-road or track use; made in USA.
Installation Notes
- Professional installation recommended.
- Reversible design simplifies center inlet/outlet routing on rotary setups.
- Compatible with standard 3in exhaust clamps; custom fabrication may be needed for direct fit.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 1979-1985 | Mazda | RX-7 | All Rotary |
| 1986-1991 | Mazda | RX-7 | FC All |
| 1993-2002 | Mazda | RX-7 | FD All |
| 2004-2011 | Mazda | RX-8 | All Rotary |
Why Choose Borla?
- Pioneer and leader in stainless steel exhaust since 1970s for classics to modern racers.
- Delivers proven power, torque gains, and signature racing sound worldwide.
- Engineered with precision for durability, flow, and motorsport victories.
Frequently Asked Questions
-
Q: Will this muffler fit my Mazda RX-7 or RX-8?
A: Yes, built for rotary engines in RX-7 1979-2002 and RX-8 2004-2011; universal 3in center setup adapts easily. -
Q: What material and build quality?
A: T-304 stainless steel with full welds and CFF core for rust-free performance and sound tuning. -
Q: What about warranty and install?
A: Borla million-mile warranty; pro install advised for optimal rotary exhaust alignment.
Shipping & Handling
- Method: UPS Ground
- Availability: In stock - ships same or next business day
- Packaging: Protective box 22in x 8in x 8in
- Weight: 11 lbs
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