The Borla XR-1 Multi-Core is a compact hot-rod racing muffler with a 2.5in center inlet and 2.5in center outlet on a 4in round body (12in body, 17in overall). Its patented Multi-Core 3-tube design flows better than straight tubing for maximum horsepower and torque, while the slim 4in body suits tight chassis packaging. T-304 stainless with CFF acoustic packing and a reversible design.
| Type | XR-1 Multi-Core racing muffler |
| Inlet/Outlet | 2.5in inlet / 2.5in outlet |
| Configuration | Center / Center |
| Body | Round - 4in diameter - 12in body - 17in overall |
| Core | Patented Multi-Core 3-tube |
| Material | T-304 stainless steel - 100% welded - natural mill finish |
| Part Number | 401384 |
Shipping: In-stock orders placed before 4 PM EST ship the same day, with standard, expedited, and overnight options available at checkout. Backordered items ship as soon as our distributor restocks — contact us for lead times. See the full Shipping Policy.
Returns: 30-day returns on new, unused items in original packaging. See the full Refund Policy.
