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Flowmaster American Thunder Crossmember-Back Exhaust System

Fits 1967-1972 Chevrolet/GMC K10, K15/K1500, K20, K25/K2500 4WD Trucks with V8 Engines, 2.50" 409 Stainless Steel

Part # 817940

Flowmaster American Thunder Crossmember-Back Exhaust System

In Stock
Free Shipping - Lower 48 US States
$881.95
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Delta Flow
5

Emissions

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.

See Emissions Details
This Flowmaster American Thunder dual exhaust system is specifically designed for 1967-1972 Chevrolet and GMC K10, K15/K1500, K20, and K25/K2500 4wd trucks with V8 engines. The system is perfect for the person looking for an aggressive to moderate interior and exterior sound level. Starting at the crossmember-back, the exhaust comes complete with a built-in H-pipe crossover for better exhaust scavenging, all mandrel-bent 2.50-inch stainless steel tubing, a pair of Super 44 Series performance mufflers, and your choice of three tailpipe exits (Turndown behind rear tires, side exit behind rear tires, or straight out the back under the bumper). The system includes all hardware necessary for installation and is covered by our Lifetime Limited Warranty. Fits both short and long wheelbase trucks.

Features:

  • Crossmember-Back Design Works with Stock Manifolds or Headers, Allowing More Application Options
  • 16-Gauge, 2.50-Inch 409 Stainless Steel Pipes add Durability and Strength
  • Super 44 Mufflers Deliver Increased Performance and an Aggressive to Moderate Sound Level
  • Three Different Tailpipe Exit Options Allow You to Tailor the Look of the Kit to Your Style
  • Mandrel-Bent Pipes Help to Maximize the Exhaust Flow for Better Performance
  • H-Pipe Style Crossover Helps Exhaust Gas Scavenging and Reduces Drone
  • Includes Hangers and Hardware for Installation
  • Lifetime Limited Warranty

About Flowmaster

Shop the official site of Flowmaster for exhaust systems, mufflers, and more that deliver the iconic Flowmaster sound. Available at Holley.com!

Brand Flowmaster
Emission Code5
Exhaust SeriesAmerican Thunder
Exit PositionDOR/S
Heat ShieldNo
Material409 Stainless Steel
Mount TypeUses New Hangers (Included)
Muffler Body Length (in)13.5
Muffler ColorBlack
Muffler FinishPainted
Muffler Inlet Diameter (in)2.5
Muffler Inlet LocationOffset
Muffler Material409S Stainless Steel
Muffler Outlet Diameter (in)2.5
Muffler Overall Length (in)19.5
Muffler Part NumberKit Only
Muffler Quantity2
Muffler SeriesSuper 44
Muffler ShapeOval
Muffler TypeReflection
Product TypeExhaust System
Sale CategoryExhaust
Single DualDual
Sound LevelAggressive / Moderate
System TypeCrossmember-back
Tip StyleNot Included
Tubing Diameter (in)2.5
Tubing Material409S Stainless Steel
UPC090127117200
California Proposition 65 Chemical NameChromium (hexavalent compounds)
Nickel (Metallic)
California Proposition 65 RequiredYes
Part Number817940
5

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.
Manifold down pipes and header reducers not included. Fits both long and short bed trucks.

*Free Shipping & Handling only offered to the contiguous US on orders over $149, excludes clearance parts and oversized packages.

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