Installation Time
(approx) 2 Hours
Difficulty Level:
Light to Moderate mechanical skill required.
Installation Guides
No guide available for this part yet.
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Flowmaster Outlaw Axle-Back Exhaust System with Polished Tips (24-26 Mustang EcoBoost w/o Active Exhaust)Find parts that fit my vehicle
Item 438421-23
Our Price
$1,065.95 set
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Product Information
Features, Description, Reviews, Q&A, Specs & Installation
Features & Specs
- Flowmaster Outlaw Axle-Back 3.00-Inch Mandrel Bent 409 Stainless Steel Exhaust System
- Dual 4.00-Inch Polished 304 Stainless Steel Tips without Valves
- Aggressive Exhaust Tone with Improved Performance
- Max Dyno Gains of Up to 8 Hp and 7 Lb-Ft at Rear Wheels
- Uses Factory Mounting Locations for Easy Installation
- Includes All Necessary Hardware
- Fits 2024-2026 Mustang EcoBoost 2.3L and GT 5.0L Models Without Active Valve Exhaust Systems
| Brand | Flowmaster |
| Exhaust System Type | Axle-Back System |
| Exhaust System Material | Stainless Steel |
| Exhaust System Tip Finish | Chrome, Polished |
| Exhaust System Tubing Diameter | 3.00 Inch |
| Exhaust Loudness | Aggressive |
Description
Performance Exhaust System. The Flowmaster Outlaw Axle-Back Exhaust System with polished tips delivers an aggressive exhaust tone and notable power gains. Designed to replace the factory non-valved axle-back exhaust, it improves flow and performance while enhancing the vehicle’s sound and appearance.
Construction and Appearance. Crafted from durable 409 stainless steel tubing with mandrel bends, the system ensures maximum exhaust flow and corrosion resistance. It features dual 4.00-inch polished 304 stainless steel tips for a refined, custom look that complements the vehicle’s design.
Installation. Installation is straightforward, utilizing factory hanger locations and including all necessary hardware. No modifications or drilling are required, allowing for a hassle-free at-home installation.
Warranty. Backed by a lifetime limited warranty, providing long-term assurance for quality and durability.
Application. Designed specifically for 2024-2026 Mustang EcoBoost 2.3L and GT 5.0L models without active valve exhaust systems.
Flowmaster 818163
CA Residents: 
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
Installation & What's in the Box
Installation Info
What's in the Box
- (1) Left Muffler Assembly
- (1) Right Muffler Assembly
- (2) Polished Exhaust Tips
- (2) Band Clamps
- Instruction Manual
Tech Guides:
- What Are the Best Mustang Exhaust Systems for Sound and Performance?
- Which Ford Mustang Axle-Back Exhaust Fits Your Sound Profile?
- What You Need To Upgrade Your Mustang Exhaust System
- What are the Benefits of Aftermarket Exhaust Systems
- Cat-Back vs Axle-Back Exhaust
- Does Upgrading an Exhaust Increase Horsepower?
- Best Mustang Cat-Back Exhaust Systems: Borla vs. Corsa vs. Magnaflow vs. Flowmaster Compared
- What Is Active Exhaust? Benefits, Modes & Upgrade Guide
- How to Improve Your Car's Exhaust Sound
- What is the Best Metal for Aftermarket Exhaust Systems
- Corsa Extreme vs. Borla Atak for Mustang
- Do Exhaust Systems Affect Fuel Efficiency?
- The Best Exhaust Systems for Maximum Horsepower Gains
- Top 5 Loudest Exhaust Systems for Your Mustang
- What are the Performance Benefits of Upgrading to a Cat-Back Exhaust
- 2024 Mustang Exhaust Guide
4.8
Customer Reviews (500+)
Questions & Answers
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Will It Fit My Mustang
- EcoBoost - 24, 25, 26
