Free shipping on ALL orders! - Details
1967-74 Camaro, Firebird, 1968-74 Nova - American Thunder Exhaust System 17104, 817104YouTube Button

Flowmaster American Thunder Header-back Exhaust System

1967-1974 Chevrolet Camaro, Pontiac Firebird with V8 engine. 2.50 inch Stainless Steel

PART# 817104

Be the first to write a review
$828.00   Suggested Retail
$744.95   Your Price
Free Shipping
In Stock  
Add to Wish List

Starting at $66 a month with Learn More
Moderate sound


Flowmaster® is proud to introduce our American Thunder® dual exhaust system for 1967-1974 Chevrolet Camaro, Pontiac Firebird and 1968-1974 Chevrolet Nova's. This all stainless steel exhaust system features our exclusive design 80 Series™ Crossflow muffler, all mandrel-bent dual 2.50-inch head pipes including an H-pipe crossover for a deep smooth tone that also minimizes any back-rap on deceleration. The dual 2.50-inch stainless steel tailpipes provide a deep rich sound and optimum performance. This header-back 409S stainless system gives these classic muscle cars a moderate tone inside and out. Using the crossflow design, this exhaust places the muffler in the factory location behind the rear axle retaining full ground clearance under the car while offering all the performance benefits of a full dual exhaust system. The system includes all parts, hardware and illustrated instructions, and like all Flowmaster stainless steel street products, it includes our Limited Lifetime Warranty.


  • H-pipe Crossover for Maximum Power and Deep Tone
  • Includes Hangers and Hardware for Easy Installation
  • 80 Series Cross-flow Performance Muffler
  • Mandrel-bent Stainless Steel Tubing
  • Moderate Exterior Exhaust Tone
  • Maximum Ground Clearance
  • Stainless Steel Construction
  • Lifetime Limited Warranty
  • Header-back System


Emission Code3
Exhaust SeriesAmerican Thunder
Exit PositionDual Out Rear
Heat ShieldNo
Inlet Diameter (in)2.5
Material409 Stainless Steel
Muffler Part NumberKit Only
Muffler Quantity1
Muffler Series80 Series Crossflow
Outlet Diameter (in)2.5
Product TypeExhaust System
Single DualDual
Sound LevelModerate
System TypeHeader-back
Tip QuantityNot Included
Tubing Diameter (in)2.5
Type of ExhaustHeader-Back
California Proposition 65 Chemical NameChromium (hexavalent compounds)
Nickel (Metallic)
California Proposition 65 RequiredYes
Part Number817104



This part is legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles and Racing Use Only Vehicles.

The following vehicles are considered Uncontrolled (Non-Emissions Controlled) Vehicles:

  • 1965 and older U.S. manufactured California Certified vehicles
  • 1967 and older U.S. manufactured Federally Certified vehicles
  • 1967 and older Foreign manufactured vehicle

The following vehicles are considered Racing Use Only Vehicles:

  • Racing Use Only Vehicles are vehicles that are used exclusively for competition and that are not registered and that may never be used on the street

WARNING: It is against the law to install this part on an Emissions Controlled Vehicle

The following vehicles are considered Emissions Controlled Vehicles:

  • 1966 and newer U.S. manufactured California Certified vehicles
  • 1968 and newer U.S. manufactured Federally Certified vehicles
  • 1968 and newer Foreign manufactured vehicle

Tech Resources

Convertible models require 3/8-inch of shims on the factory X-brace for clearance of the exhaust tubing.


We Suggest

      *Free Shipping & Handling only offered to the contiguous US on orders over $100, excludes clearance parts and oversized packages.

      Some parts are not legal for use in California or other states with similar regulations.

       X  Roadkill Buick Sweepstakes
       X  Roadkill Buick Sweepstakes