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Borla 40359 ProXS Muffler - Un-Notched Neck: 40359. ProXS Muffler 3 Offset Inlet/ 3 Center Outlet, 4 x 9.5 Oval, 14 Long Body, 19 Overall Length. Universal Part. Reversible Design. Along with the distinctive Borla Sound of Power recognized by motoring enthusiasts everywhere, upgrading your ride with a Borla exhaust gives you a boost in power and torque, improved fuel economy, longer engine life and refined motorsport styling. But most of all, Borla gives you the intoxicating rush that comes with every squeeze of the throttle, the thrill of raging power with every shift, and a heart-pounding soundtrack to match. More than anything else, we understand that we build far more than exhaust systems. We build excitement.; Along with the distinctive Borla Sound of Power recognized by motoring enthusiasts everywhere, upgrading your ride with a Borla exhaust gives you a boost in power and torque, improved fuel economy, longer engine life and refined motorsport styling. But most of all, Borla gives you the intoxicating rush that comes with every squeeze of the throttle, the thrill of raging power with every shift, and a heart-pounding soundtrack to match. More than anything else, we understand that we build far more than exhaust systems. We build excitement.
Reversible design for installation flexibility. High-quality T-304 austenitic stainless steel will never rust. 100% welded construction for strength. Free Flow design for improved performance. High-temperature continuous-filament fiber (CFF) acoustic material for sound control. Natural mill finish can be brushed or polished prior to installation.- Body Height:4.000 in.
- Body Length:14.000 in.
- Body Width:9.500 in.
- Construction:All Welded
- Grade Type:Performance
- Inlet Connection Type:Pipe
- Inlet Outside Diameter:3.000 in.
- Inlet Position:Center
- Inlet Type:Single Center
- Main Piping Diameter:3.000 in.
- Material:T-304 Stainless Steel
- Muffler Count:1
- Off Road Use Only:No
- Outlet Outside Diameter:3.000 in.
- Outlet Position:Offset
- Outlet Type:Single Offset Outlet
- Overall Length:19.000 in.
- Shape:Oval
- Tip / Outlet Finish:N/A
- Title:ProXS Muffler 3in Offset Inlet/ 3in Center Outlet 4in x 9.5in Oval x 14in Long Body
- Title Extended:ProXS Muffler 3in Offset/Center 14inx4inx9.5in Part # 40359
BORLA PERFORMANCE INDUSTRIES is the pioneer and leader in the design and manufacture of stainless steel performance exhaust. We began two decades ago as a manufacturer of exhaust systems for such "concours classics" as Rolls-Royce and Ferrari cars and have evolved into the premier manufacturer of today's performance vehicles for the street, off-road, and racing.
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Borla
Discover the Borla Exhaust collection, where world-class exhaust products meet the high standards of automotive enthusiasts. Borla is dedicated to exceeding your expectations by utilizing a state-of-the-art test and development center. This facility allows us to continually refine our manufacturing precision and maintain the highest quality standards. Our commitment to innovation is evident through numerous US patents for advanced exhaust design and multiple "Best New Product" awards in the industry.
Unmatched Customization
What sets Borla apart from other exhaust systems is our vehicle-specific design approach. Each exhaust system is meticulously crafted to accommodate the unique mechanical and acoustical properties of different cars and trucks. We invest countless hours in optimizing various components, such as:
- Muffler body shapes
- Internal core configurations
- Flow dynamics
- Sound characteristics
Exclusive Sound Technologies
Borla offers a choice of three exclusive sound technologies to match your preferences:
- ATAK: Aggressive sound for performance enthusiasts
- S-Type: A blend of performance and refinement
- Touring: A sophisticated sound for everyday driving
With the Borla collection, you can elevate your vehicle's performance and sound, ensuring a driving experience that truly stands out. Choose Borla for unparalleled quality and innovation in exhaust systems.

Exhaust Systems
Welcome to our collection of high-quality exhaust systems, designed to elevate your vehicle's performance while providing an outstanding driving experience. Our website simplifies the search for the perfect exhaust components for your vehicle, allowing you to easily browse through a wide range of custom and performance exhaust parts.
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Why Choose Our Exhaust Systems?
- Improved performance and power output.
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Our user-friendly website enables you to search by make, model, and year, ensuring you find the right components tailored to your vehicle's needs. Explore our selection of top brands:
- Banks Power
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Upgrade Your Vehicle Today!
Don't wait to enhance your vehicle's performance. Shop now and experience the difference with our premium exhaust systems!