Borla · New
Borla XR-1 Multi-Core 3in Ctr-Ctr Oval 16in x 4.25in x 7.88in Rotary Engine Equipped Racing Muffler
MPN 400371 · Store SKU bor400371
Supplier stock checked 11/7/2026, 9:59:42 AM UTC. Adding a part does not reserve it.
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Product details
XR-1(r) Multi-Core Racing Muffler. 3" Center Inlet/ 3" Center Outlet 4.25" x 7.88" Oval x 16" Long Body 21" Overall Length. Compact size is perfect for applications with limited space and can be used on a wide range of vehicles. It features BORLA(r)'S patented Multi-Core 4 tube design for maximum flow, horsepower, and torque. The Multi-Core portion of XR-1 mufflers flows better than straight tubing. Recommend for high horsepower applications. Reversible design for installation flexibility. T-304 Stainless steel for superior corrosion resistance. Natural mill finish can be brushed or polished prior to installation. 100% welded construction for strength. High-temperature continuous-filament fiber (CRF) acoustic material for sound control. There is no BORLA(r) logo embossment on this part. Best of all, it's made in the USA. Just what you’d expect from the world’s most experienced (and most winning) exhaust brand. BORLA XR-1 Raceline products are the choice of todays hottest drag and oval track racers. Featuring a patented uninerrupted-flow design and multicore technology. BORLAs XR-1 mufflers actually outflow a straight piece of pipe in repeated testing. XR-1 race products are light weight and constructed of high quality austenitic stainless steel for track-tough durability. They meet the strictest noice requirements and use sound absorbing stainless steel pcking to protect against burnout. Hands down, BORLAs XR-1 Raceline offers the best balance of sound and power. XR-1 Multi-Core Racing Muffler Rotary Engine Equipped Vehicles - 3" Center Inlet/ 3" Center Outlet 4.25" x 7.88" Oval x 16" Long Body 21" Overall Length. Universal Part. Reversible Design. XR-1® Stainless Multicore Racing Mufflers XR-1 Multicore Muffler
Manufacturer fitment & guides
Check 400371 against the manufacturer’s application information below.
Part-specific notes
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