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Flowmaster 17139 American Thunder Crossmember-Back Dual Exhaust System

(1969 Chevrolet Camaro; 1969 Pontiac Firebird)

Part of: Flowmaster American Thunder Crossmember-Back Dual Exhaust System

Other options in this family: Flowmaster 817654 Flowmaster 17201 Flowmaster 817200 Flowmaster 817174 Flowmaster 17282

Manufacturer

Picture for manufacturer Flowmaster

Part Number

17139
5 reviews
Sale Price

$899.95

In Stock (10+)

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Usually delivered within 2 days

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Product Details

The Flowmaster American Thunder Crossmember-Back Exhaust System delivers a performance upgrade with an aggressive sound profile that's perfect for enthusiasts seeking both power and presence. This true dual exhaust system is engineered to replace your factory exhaust from the crossmember back, providing improved flow and a deep, commanding exhaust note.

Key Features:

  • Super 44 Series mufflers produce a moderate to aggressive exterior tone with deep, powerful sound
  • True dual exhaust design with H-pipe crossover for maximum power gains and enhanced tone quality
  • Mandrel-bent 16-gauge aluminized steel tubing maintains consistent diameter for optimal exhaust flow
  • 2.50-inch angle cut 304 stainless steel tips provide corrosion resistance and premium appearance
  • Exits in factory location for clean, OEM-style installation
  • Complete system includes all necessary hangers and hardware for bolt-on installation

This crossmember-back system is designed for direct fit installation and utilizes factory mounting points. Note that this system does not include header reducers or manifold downpipes—it connects to your existing exhaust components at the crossmember. The combination of Flowmaster's Super 44 mufflers and H-pipe design delivers the signature American Thunder sound that balances performance with streetability.

Products specifications

Fits

1969 Chevrolet Camaro; 1969 Pontiac Firebird

Tip Diameter

2.500 in.

Outlet Outside Diameter

2.500 in.

Prop 65

WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

California Proposition 65 Chemical Name 2

Chromium (hexavalent compounds)

California Proposition 65 Chemical Name 1

Nickel (metallic)

California Proposition 65 Chemical Name

Chromium (hexavalent compounds)

California Proposition 65 Chemical Name

Nickel (Metallic)

System Type

Header Back

Heat Shield Attached

No

Material

Aluminized Steel

Tubing Diameter

2.500 in.

Outlet Diameter

2.500 in.

Muffler Count

2

Exit Position

Dual Rear

Tip Quantity

2

Tail Pipe Diameter

2.500 in.

Exhaust Type

Dual

Single or Dual

Dual

Title

Flowmaster 17139 Header-back System - Dual Rear Exit - American Thunder - Moderate/Aggressive

Brand

Flowmaster

Catalytic Converter Quantity

0

Category

Exhaust

Clamping Type

U-Bolt

Clamps Included

Yes

Drive

2WD

Emission Code

5

Exhaust Series

American Thunder

Exhaust Tip Connection

Welded

Exhaust Tip Cut

Angled

Exhaust Tip Edge

Slash Cut

Exhaust Tip Finish

Polished

Exhaust Tip Intercooled

No

Exhaust Tip Material

304 Stainless Steel

Exhaust Tip Quantity

2

Exhaust Tip Resonated

No

Exhaust Tip Shape

Round

Exhaust Tip Wall

Single Wall

Exit Style

Dual Out Rear

Finish

Aluminized

Gasket Or Seal Included

No

Grade Type

Performance

Hangers Included

Yes

Heat Shield Included

No

Inlet Diameter

2.50

Inlet Type

Weld-On

Mounting Bracket Included

Yes

Muffler (Left) Type

Chambered

Muffler (Right) Type

Chambered

Muffler Body Material

Aluminized Steel

Muffler Body Shape

Oval

Muffler Finish

Black High-Temperature Paint Finish

Muffler Flanged Inlet

No

Muffler Flanged Outlet

No

Muffler Inlet Connection

Slip-Fit

Muffler Outlet Connection

Slip-Fit

Muffler Outlet Quantity

1

muffler part number

942546

Muffler Quantity

2

Muffler Series

Super 44 Series

Muffler Type

Chambered

Pipe Color

Silver

Pipe Material

Aluminized Steel

Product Type

Exhaust System

Sound Level

Aggressive / Moderate

Spring Bolt Kit Included

No

Sub Category

Exhaust and Tail Pipes

Tail Pipe Quantity

2

Tail Pipe Quantity

Dual

Tail Pipe Tapered Outlet

No

Type

Crossmember-Back

Valve Included

No

Valve Type

Not Applicable

Warning

California Proposition 65

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