Free shipping on orders over $100 Details

Flowmaster American Thunder Header-back Exhaust System

1964-1972 Chevrolet El Camino and GMC Sprint with V8 engine, 2.5" Aluminized pipes

PART# 17120

Be the first to write a review
$702.00   Suggested Retail
$630.95   Your Price
Estimated shipping date: 03/08/2021
Email Me When Available
Free Shipping
Add to Wish List

Starting at $56 a month with Learn More
Delta Flow
Aggressive to moderate sound


For the person who is looking for a complete headers-back dual exhaust system with a moderately aggressive tone. With easy fit in mind, these systems are constructed from 2.50-inch mandrel-bent aluminized steel with a built in H-pipe to equalized the exhaust pressures, eliminates backrap on deceleration and makes maximum power. The system includes a pair of specially selected Super 50 Series mufflers for a deep powerful exterior sound with minimal interior tone and is suited for the enthusiast who wants their performance to be heard, just not inside the cab. The mandrel-bent tailpipes exit at an angle behind the rear wheels and are finished off with large 3.00-inch angle cut polished stainless tips for an aggressive look. Like all Flowmaster systems, the benefits include improved throttle response, power and mileage. Designed for an easy fit, these systems include all necessary parts and hardware for easy installation.


  • Includes Hangers and Hardware for an Easy Installation
  • Super 50 Series Performance Mufflers Eliminates Drone
  • Mandrel-bent 16-gauge Aluminized Steel Tubing
  • Moderate to Aggressive Exterior Exhaust Tone
  • Dyno Tuned for Maximum Performance
  • Polished 3.00-inch Stainless Steel Tips
  • Includes H-pipe Assembly


Emission Code3
Exhaust SeriesAmerican Thunder
Exit PositionDual Side Exit
Heat ShieldNo
Inlet Diameter (in)2.5
MaterialAluminized Steel
Muffler Part Number52558
Muffler Quantity2
Muffler SeriesSuper 50 Series
Outlet Diameter (in)2.5
Product TypeExhaust System
Single DualDual
Sound LevelAggressive / Moderate
System TypeHeader-back
Tip Diameter (in)3
Tip Quantity2
Tubing Diameter (in)2.5
California Proposition 65 Chemical NameChromium (hexavalent compounds)
Nickel (Metallic)
California Proposition 65 RequiredYes
Part Number17120



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

Fits 1964-1972 Chevrolet El Camino and GMC Sprint with V8 engine.


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  Sloppy Mechanics Sweepstakes
       X  Sloppy Mechanics Sweepstakes