Borla Universal Pro-XS 2.25-Inch Dual Inlet / Dual Outlet Polished T-304 Stainless Steel Oval Muffler with Internal X-Pipe (400287)
Unlock ultimate exhaust flow and aggressive acoustic tuning with the Borla Universal Pro-XS Muffler. Masterfully engineered to meet the demanding requirements of high-horsepower track setups, race cars, performance trucks, and customized SUVs, this high-efficiency unit utilizes a bidirectional dual-in and dual-out 2.25-inch configuration. At its mechanical core, this premium racing muffler breaks away from restrictive traditional baffle layouts by incorporating Borla’s cutting-edge internal X-pipe geometry. This innovative layout features an integrated crossover network that balances exhaust pulses between cylinder banks, generating an excellent scavenger effect. This advanced aerodynamic design maximizes peak horsepower, expands torque delivery, and completely eliminates backpressure bottlenecks for dual-exhaust configurations.
The structural engineering of the Borla 400287 addresses long-term durability and installation problems beneath harsh track and street conditions through a 100% welded, heavy-gauge setup. Enclosed in a substantial 4-inch by 9.5-inch oval by 19-inch long barrel case with a total 24-inch overall footprint, this robust assembly delivers excellent space optimization when tucked into narrow transmission tunnels, custom driveshaft loops, or crowded truck frames. The specialized dual-crossover body layout packs a massive volume of advanced, high-temperature Continuous-Filament Fiber (CFF) acoustic sound control packing. This advanced insulation filters out high-frequency rasp and annoying highway cabin drone while preserving a raw, unrestrictive mechanical tone under full throttle. Built completely from aircraft-quality, premium-grade T-304 austenitic stainless steel finished in a natural mill texture with smooth, un-notched neck bases, this heavy-duty canister accommodates custom brush or mirror-polished workshop textures prior to installation. Capable of being flipped or reverse-mounted due to its completely uniform, reversible internal configuration, this elite USA-made performance component delivers bulletproof structural stability backed by Borla’s legendary Million-Mile warranty.
Integrated Internal X-Pipe Crossover Dynamics: Unlike basic dual-inlet mufflers that keep exhaust banks isolated, this Pro-XS unit features a built-in cross-flow internal X-pipe network. This dual-crossover layout uses precise perforation matrices to sync exhaust gas pressures from both sides of the engine, breaking down high-energy sound waves and enhancing low-end torque without placing a physical restriction in the path of the thermal gas exit.
Fabrication Installation Guideline Note: This high-performance universal muffler is built with smooth, un-notched attachment necks engineered for permanent weld-on workshop connection. If your project demands a removable mechanical configuration instead of a fixed weld joint, the smooth connection collars can easily accommodate heavy-duty, wide two-bolt style band clamps (clamps not included). If you prefer factory-notched slip-fit connections for standard clamps, see alternate part number 400492.
Features
- Integrated Internal Crossover: Built-in internal X-pipe equalizes exhaust pulses for improved scavenging, extra torque, and a smoother exhaust note
- High-Flow Dual-In/Dual-Out Track Configuration: Matched 2.25" dual ports provide an all-in-one mid-muffler solution for clean dual-exhaust routing
- Premium Continuous-Filament Fiber: Packed with high-temp CFF insulation to absorb harsh acoustic frequencies while maintaining a deep, muscular tone
- Smooth Un-Notched Neck Bases: Engineered explicitly for high-strength welding or simple adaptation with heavy-duty wide band clamps
- 100% Symmetrical Reversible Layout: Bidirectional configuration provides ultimate fabrication flexibility, allowing it to be installed in either direction
- Heavy-Duty 100% Welded Body: Fully welded seams deliver maximum structural strength to resist extreme backfire pressures and track vibrations
- Constructed completely from premium-grade T-304 austenitic stainless steel for permanent structural integrity and ultimate rust resistance over low-grade 400-series hardware options
- Proudly Manufactured in the USA: Built in America by the world’s most experienced exhaust brand to guarantee flawless fitment and elite race-proven quality
Detailed Fitment Breakdown
Universal Application Parameters & Structural Boundaries:
This premium universal Pro-XS dual muffler with built-in X-pipe is compatible with a massive array of custom and production vehicle platforms under the specific architectural parameters detailed below:
Universal Automotive & Custom Exhaust Fabrication Fitment:
- Integrates seamlessly into any custom aftermarket or factory replacement dual exhaust line running 2.25-inch piping
- Sized perfectly for center-mounted single-muffler dual tracks on high-output trucks, performance SUVs, and true-dual muscle cars
- Highly recommended for V6 and V8 applications requiring an integrated crossover mid-section to clean up exhaust rasp and drone
- Compatible across all domestic and import car, truck, and SUV platforms with sufficient clearance for a 4" x 9.5" oval body footprint
Sizing, Connection & Dimensional Details:
Fits your project layout across these exact structural specifications:
- Inlet / Outlet Connection Size: Dual 2.25-Inch internal diameter ports at both ends
- Muffler Case Configuration: 4.00-Inch x 9.50-Inch traditional oval structural shape
- Muffler Case Body Length: 19.00 Inches of primary sound suppression coverage
- Overall Muffler Total Length: 24.00 Inches from inlet tip to outlet tip boundary
- Internal Architecture Matrix: Straight-through high-flow dual X-pipe configuration with CFF sound material
- Material Grade Composition: Authentic T-304 Austenitic Stainless Steel with a natural mill finish
Important Application Notes:
- **Premium Materials:** Built entirely with authentic T-304 stainless steel to deliver superior rust resistance and durability over lower-grade T-400 series or aluminized hardware choices.
- **Versatile Fabrication Paths:** Engineered as a professional universal component requiring basic cutting and welding modifications, providing custom fabricators with a dependable, heavy-walled material block that stands up to severe under-car heat cycles without fracturing.
CA Residents: WARNING: Cancer and Reproductive Harm www.P65Warnings.ca.gov
