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Borla XR-1 Multi-Core 3in Ctr-Ctr Round 16in x 6.25in Rotary Engine Equipped Racing Muffler-Borla-BOR400373
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Borla XR-1 Multi-Core 3in Ctr-Ctr Round 16in x 6.25in Rotary Engine Equipped Racing Muffler

Borla
BOR400373
808422003735
Muffler
11 Units In Stock - Ships Next Business Day
$ 335.99 $ 299.99
FREE Ground Shipping!
$ 299.99

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

Request For Information

Have questions about Borla XR-1 Multi-Core 3in Ctr-Ctr Round 16in x 6.25in Rotary Engine Equipped Racing Muffler? Fill out the form below and we'll get back to you by the next business day.
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