The unmistakable rumble of a muscle car is more than just noise—it’s the heartbeat of an era. And if you’re restoring a classic GM A-Body, the exhaust note isn’t just a detail; it’s the finishing touch.

The Flowmaster 17119 American Thunder Crossmember-Back Exhaust Kit is one of the most sought-after systems for 1964–1972 GM A-Body vehicles, offering not just sound but a legitimate boost in performance and driving feel.

Whether you’re working on a Chevelle, GTO, Cutlass, or another GM icon, this guide breaks down everything you need to know about the Flowmaster 17119: specs, fitment, installation, sound profile, performance gains, and real-world value.

Why This Exhaust Kit Has Become a Restoration Staple

Engineered for classic muscle but packed with modern upgrades, the Flowmaster 17119 isn’t just popular because of the brand name—it earns its reputation where it matters most: performance, durability, and tone.

Key Features and Specifications

• 16-gauge mandrel-bent aluminized steel tubing for consistent flow
  
• 2.5-inch dual exhaust system with full crossmember-back configuration
  
• Includes Flowmaster Super 40 Series mufflers for an aggressive tone
  
• Dual rear exit design—choose between slash cut or turndown tailpipes
  
• Full installation hardware, H-pipe, and instructions included
  
• 3-year limited warranty from Flowmaster
  

This system is designed to integrate seamlessly with aftermarket long tube headers and offers a complete solution from front to back, eliminating the need for custom fabrication.

Compatible With the Classics That Matter Most

Fitment is one of the strongest points of the Flowmaster 17119. It’s designed with popular GM A-Body V8 models in mind.

Supported Models Include:

• Chevrolet: Chevelle, El Camino, Malibu, Monte Carlo
  
• Pontiac: GTO, LeMans, Tempest
  
• Oldsmobile: 442, Cutlass
  
• Buick: Skylark, Gran Sport
  

Keep in mind, this system doesn’t work with factory manifolds or stock downpipes.

You’ll need aftermarket long tube headers for proper installation, and in some cases, minor adjustments may be required for the best fit.

What You’ll Hear and Feel Behind the Wheel

The H-pipe configuration equalizes exhaust flow from both sides, smoothing out performance while boosting horsepower and torque.

Benefits Go Beyond Volume:

• Power increases up to 10% in most setups
  
• Noticeably sharper throttle response
  
• Deep, throaty idle that escalates to a roaring growl under load
  
• Maintains interior comfort without excessive drone
  
• Reduced exhaust restriction, improving engine breathing
  

The Super 40 Series mufflers strike a balance between raw muscle and road-trip civility, making this system a favorite for both weekend cruises and daily drives.

Installation: Doable for Most Enthusiasts

With the right tools and a little time, most garage-savvy owners can handle the install themselves. Just be prepared for a few tight spots and test fits.

What You’ll Need:

• Basic hand tools
  
• Reciprocating saw and measuring tape
  
• Welding equipment (optional but recommended for some joints)
  
• A lift or quality jack stands
  

Plan for about 3–4 hours if you’re experienced. The included instructions are detailed enough to guide most through the process, though beginners might benefit from some assistance.

Built to Handle the Heat—and the Years

Durability is a core part of this kit’s appeal. Flowmaster used solid materials and thoughtful design to ensure long-term performance.

• 16-gauge aluminized steel resists heat and corrosion
  
• Mandrel bends prevent bottlenecks in flow
  
• Fully-welded mufflers hold up under high-temp driving
  
• Heavy-duty hangers prevent sag and maintain alignment
  

For anyone driving in harsh conditions—or just wanting peace of mind—the 3-year warranty is a welcomed addition.

The Price Tag: Why This Kit Wins on Value

Among pre-configured exhaust kits, Flowmaster’s offering is hard to beat.

• Amazon: $707.46 with free returns
  
• Flowmaster website & Summit Racing: $779.95 (Summit includes free shipping)
  
• Chevelle Depot (Canada): $1,220.99 CAD
  

When compared to custom setups costing well over $1,200, this kit gives you premium sound and performance at a much lower cost. And it includes everything you need out of the box.

Verified Gains from Real Drivers

It’s not just marketing speak—drivers are seeing measurable improvements.

• Reported 10–15 HP increases in typical builds
  
• 1–2 MPG gains on the highway
  
• Better throttle response and smoother acceleration
  
• Cooler engine temps due to better exhaust flow
  
• Deep, satisfying sound without unwanted drone
  

Owners often cite the perfect blend of volume and tone, describing it as the “muscle car soundtrack” they were after all along.

The Best Upgrade for Your Classic? It Just Might Be

The Flowmaster 17119 American Thunder Exhaust Kit offers everything a GM A-Body owner could want: bold sound, real power improvements, long-lasting materials, and a fit tailored to classic V8 platforms.

If you’re restoring or upgrading a classic ride and want an exhaust that lives up to the look and legacy of your muscle car, this system is worth serious consideration.

The competitive price on Amazon only strengthens the case, making it a smarter investment than most custom alternatives.

Stock might be fine for a cruiser, but if you want to build a car that feels alive—this is the kind of upgrade that makes all the difference.