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Flowmaster Header-back System 409S - Dual Side Exit - American Thunder - Aggressive Sound

$745.00 Sale:$669.95

Flowmaster

Model #817412

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Shopper Award

This product is for Racing Competition only and is not legal for use in highway or street vehicles or other non-racing competition off-road vehicles.

Purchasing this product requires you to sign our Vehicle Compliance Waiver here.

For the person who is looking for a complete Header-back dual exhaust system with an aggressive tone. With easy fit in mind, these systems are mandrel bent for maximum performance and include specially selected mufflers. American Thunder systems deliver a moderate to aggressive interior and exterior tone and are suited to the enthusiast who wants their performance to be heard. 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.

Features:

  • H-pipe Crossover for Maximum Power and Deep Tone
  • Super 40 Series Mufflers for Deep Powerful Sound
  • Mandrel-bent 16-gauge Stainless Steel Tubing
  • Includes Hangers and Hardware for Installation
  • Moderate to Aggressive Exterior Exhaust Tone
  • Header-back True Dual Exhaust System
  • Does Not Include Header Reducers
  • Lifetime Limited Warranty
Specifications:
  • 2WD/4WD: 2WD
  • California Proposition 65 Chemical Name: Chromium (hexavalent compounds)
  • California Proposition 65 Chemical Name: Nickel (Metallic)
  • California Proposition 65 Required: Yes
  • Emission Code: 3
  • Exhaust Series: American Thunder
  • Exit Position: Dual Side Exit
  • Heat Shield: No
  • Inlet Diameter (in): 2.5
  • Material: Stainless Steel
  • Muffler Part Number: Kit Only
  • Muffler Quantity: 2
  • Muffler Series: Super 40 Series
  • Outlet Diameter (in): 2.5
  • Product Type: Exhaust Systems / Kits
  • Single Dual: Dual
  • Sound Level: Aggressive Sound
  • System Type: Header-back System
  • Tip Quantity: Not Included
  • Tubing Diameter (in): 2.5
  • Type of Exhaust: Header-Back
  • Warning: California Proposition 65
Notes:
  • Fits 1964-1967 GM A-Body with V8 engine.

Proposition 65

/!\ warningWARNING: Cancer and Reproductive Harm

https://www.P65Warnings.ca.gov

Vehicle Engine Notes
1967
Buick Gran Sport

8 Cylinder 5.6 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1965-1967
Buick Gran Sport

8 Cylinder 6.6 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1964-1967
Buick Skylark

8 Cylinder 4.9 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1966-1967
Buick Skylark

8 Cylinder 5.6 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1965-1967
Buick Skylark

8 Cylinder 6.6 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1964-1967
Buick Special

8 Cylinder 4.9 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1965, 1967
Chevrolet Chevelle

8 Cylinder 5.4 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1965, 1967
Chevrolet Chevelle

8 Cylinder 4.6 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1965, 1967
Chevrolet Chevelle

8 Cylinder 6.5 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1965, 1967
Chevrolet Chevelle

8 Cylinder 5.3 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1964, 1966
Chevrolet Chevelle
Base
8 Cylinder 4.6 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1964, 1966
Chevrolet Chevelle
Base
8 Cylinder 5.3 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1966
Chevrolet Chevelle
Deluxe
8 Cylinder 4.6 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1966
Chevrolet Chevelle
SS
8 Cylinder 6.5 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1964-1967
Oldsmobile F85

8 Cylinder 5.4 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1964-1967
Oldsmobile Vista Cruiser

  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1967
Pontiac GTO

8 Cylinder 6.6 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1964-1966
Pontiac GTO

8 Cylinder 6.4 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use
1964-1967
Pontiac LeMans

8 Cylinder 5.3 Liter
  • Dual; Dual Side Exit; Incl. 2.5 in. Tubing/Super 40 Series(TM) Mufflers/H-Pipe/Hardware; 409 Stainless Steel;Legal On Non-Emissions Controlled Vehicles Or For Race Use

Who is Flowmaster?

Flowmaster is an aftermarket company that was founded in 1983. The company specializes in manufacturing high-performance exhaust systems for various vehicles. This includes classic muscle cars, modern sedans, trucks, jeeps, off-road vehicles, and more. 

It has since revolutionized the industry and has continued its tradition to produce high-quality exhaust parts. Today, Flowmaster has been the go-to brand of many car builders and enthusiasts worldwide and has been the market leader for years.

Pushing the Boundaries of Exhaust Design

Flowmaster has been the pioneer when it comes to developing mufflers. They produce mufflers that are quiet enough to be used legally on the streets but, at the same time, does not restrict the performance of the engine. This is why more and more people are choosing Flowmaster for their car builds as they can enjoy their vehicles on and off the streets.

An Exhaust For Any Style

The company provides its customers with the ability to choose the type of muffler they want. They offer five sound categories of their exhaust system, from quiet and discrete to something more aggressive and gives that racy sound. They can also choose between 12 designs of chambered mufflers, including their exclusively-designed “laminar-flow” muffler or “straight-through.”They also have a custom-built exhaust system for that one-of car builds.

Passionate Development Team

Flowmaster is composed of people who have years of experience in developing quality exhaust systems. Using the knowledge they acquired over the years, they improved their designs and matched it with the ever-growing technological advancement of vehicles today. 

Tried and Tested

With hundreds of installs under its belt, Flowmaster has proven itself to be a brand that delivers what it promised. In addition, all their exhaust systems are designed and dyno-tested, ensuring that they can maximize your vehicle’s performance once installed. 

Purchase Flowmaster at Vivid Racing

If you are in the market for an upgrade in your vehicle’s exhaust that would provide you with that distinct sound and improved performance, then Flowmaster is the brand for you. To know more about Flowmaster, visit Vivid Racing and check out their list of products that fit your requirement.




LIMITED WARRANTY:

This catalytic converter is warranted to be free from defects in materials andworkmanship subject to the exclusion and conditions set forth below and subject to the durational limits in this paragraph. This catalytic converter has been designed and manufactured and is warranted to meet federal Environmental Protection Agency emission requirements for 25,000 miles. The stainless steel body and the nipples alone are warranted for 5 years or 50,000 miles, whichever comesfirst. At the conclusion of the 5 year/50,000 mile or 25,000 mile period, whichever is applicable, all liability under this limited warranty shall terminate.

For full warranty information Click Here

Installation Instructions

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Warranty Information

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