The Borla ProXS notched-neck muffler is a universal-fit part with a 3-inch offset inlet and 3-inch offset outlet in a 4-inch by 9.5-inch oval case with a 14-inch body and 19-inch overall length. Its notched necks are made for clamp-on installation. The design is reversible for installation flexibility.
Part number: 400491
Borla muffler.
Reversible design for installation flexibility. 100% welded construction for strength. Free Flow design for improved performance. High-temperature continuous-filament fiber (CFF) acoustic material for sound control. Alternate muffler with Un-Notched necks is 40353.
Manufacturer data for this part — all visible, no tabs to dig through.
| Brand | Borla |
| Part number | 400491 |
| Material | T-304 Stainless Steel |
| Shipping carton | 5 × 10 × 20 in (13 × 25 × 51 cm) |
| Shipping weight | 4.5 kg (10 lb) |
| Product dimensions | Length 18 in (45.7 cm) |
| Grade type | Performance |
| Construction | All Welded |
| Body width | 9.500 in |
| Body height | 4.000 in |
| Outlet outside diameter | 3.000 in |
| Overall length | 18.000 in |
| Outlet type | Single Offset Outlet |
| Outlet position | Offset |
| Body length | 14.000 in |
| Muffler count | 1 |
| Main piping diameter | 3.000 in |
| Inlet type | Single Offset |
| Inlet position | Offset |
| Inlet outside diameter | 3.000 in |
| Category | Exhaust & Performance |
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