The Borla XR-1 Multi-Core racing muffler is a universal-fit part with a 3-inch center inlet and 3-inch center outlet in a 6.25-inch round case with a 16-inch body and 21-inch overall length. The long body suits SUV and truck applications.
Part number: 400373
Borla muffler.
XR-1® Multi-Core Racing Muffler. It features BORLA®'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. 100% welded construction for strength. High-temperature continuous-filament fiber (CFF) acoustic material for sound control. There is no BORLA® logo embossment on this part. Just what you’d expect from the world’s most experienced (and most winning) exhaust brand.
Manufacturer data for this part — all visible, no tabs to dig through.
| Brand | Borla |
| Part number | 400373 |
| Material | T-304 Stainless Steel |
| Country of manufacture | United States |
| Shipping carton | 6 × 10 × 24 in (15 × 25 × 61 cm) |
| Shipping weight | 5.4 kg (12 lb) |
| Product dimensions | Length 21 in (53.3 cm) |
| Body height | 6.250 in |
| Outlet outside diameter | 3.000 in |
| Shape | Round |
| Overall length | 21.000 in |
| Outlet type | Single Center Outlet |
| Outlet position | Center |
| Body length | 16.000 in |
| Muffler count | 1 |
| Main piping diameter | 3.000 in |
| Inlet type | Single Center |
| Inlet position | Center |
| Inlet outside diameter | 3.000 in |
| Grade type | Performance |
| Construction | All Welded |
| Body width | 6.250 in |
| Category | Exhaust & Performance |
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