SKU: 400477 | UPC: 808422504775
Borla 400477 ProXS Muffler 2in Offset Inlet/2in Center Outlet 4.25x7.88 Oval 14in Body Notched Necks - Universal
The Borla 400477 ProXS Muffler delivers aggressive exhaust tone with power gains, torque increases and better fuel economy for custom street and performance builds. This universal oval muffler fits tight spaces on most vehicles with 2in piping via reversible notched necks. T304 stainless steel construction ensures durability while the free-flow design enhances throttle response and engine efficiency.
Key Features
- Notched Necks: Enable direct clamp-on fit to 2in tubing for quick, no-weld installs on custom exhausts.
- Compact Oval Shape: 4.25in H x 7.88in W x 14in body length fits restricted areas, overall 18in long.
- Reversible Design: Offset inlet/center outlet or flip for center inlet/offset outlet flexibility in any setup.
- T-304 Stainless Steel: Corrosion-resistant material with 100% welded build withstands heat and road abuse.
- Free-Flow with CFF Core: High-flow tubes and continuous-filament fiber packing control sound while delivering power and torque boosts.
Product Notes
- Notched necks simplify clamp-on attachment without fabrication.
- Mill finish allows brushing or polishing before install for custom look.
- Securely packaged for damage-free delivery.
Installation Notes
- Professional installation recommended.
- Clamp directly to 2in piping; reversible ends support left/right orientation.
- Compatible with standard exhaust clamps and hangers; no welding required.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | All Makes | All Models | Custom Exhaust Applications |
Why Choose Borla?
- Leaders in stainless steel exhaust since 1978, starting with Ferrari and Rolls-Royce systems.
- Engineered for real-world power, torque and fuel economy gains with signature sound.
- Precision mandrel-bent and fully welded for leak-free performance in street or racing.
Frequently Asked Questions
-
Q: Will this muffler fit my vehicle?
A: Universal design works on most cars, trucks and SUVs with 2in piping and sufficient underbody clearance; measure for 4.25x7.88x14in body space. -
Q: What material is used and does it rust?
A: T-304 austenitic stainless steel provides lifetime rust resistance with high-heat tolerance and mill finish option for polishing. -
Q: What warranty covers this muffler?
A: Backed by Borla's limited lifetime warranty against defects in materials and workmanship for original purchaser.
Shipping & Handling
- Method: UPS Ground or FedEx Ground
- Availability: In stock - ships same or next business day
- Packaging: Box dimensions 20in x 10in x 10in
- Weight: 7.6 lbs

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