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Flowmaster

Flowmaster 817409 American Thunder Crossmember-Back Exhaust System

Flowmaster 817409 American Thunder Crossmember-Back Exhaust System

Regular price $1,117.95 USD
Regular price Sale price $1,117.95 USD
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Description & Features

Flowmaster 817409 American Thunder Crossmember-Back Exhaust System

This American Thunder® exhaust system comes as a complete true dual Crossmember-Back exhaust for your 1968-1972 GM A-body with a V8 engine. These dual exhaust systems feature 2.50-inch mandrel-bent stainless steel tubing for maximum performance, includes a built-in H-pipe/balance tube flowing into a pair of large case Super 40® mufflers that deliver an aggressive interior and exterior tone and are suited to the enthusiast who wants their performance to be heard. The 2.50-inch tailpipes exit at a slight angle down under the rear bumper for a strong muscular look. The system includes all hangers and necessary hardware for installation. Like all Flowmaster® systems, the benefits include improved throttle response, power and mileage and is covered by our Lifetime Limited Warranty.

  • 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
  • Aggressive Exterior Exhaust Tone
  • Crossmember-Back True Dual Exhaust System
  • Does Not Include Header Reducers or Downpipes for Factory Manifolds
  • Lifetime Limited Warranty
Specifications
Brand Flowmaster
California Proposition 65 Yes
California Proposition 65 Chemical Name Chromium (hexavalent compounds)
CARB (California) Compliant Yes
Catalytic Converter Included No
Catalytic Converter Quantity 0
Category Exhaust
Clamping Type Flat Band
Clamps Included Yes
Drive 2WD
Emission Code 5
Exhaust Series American Thunder
Exhaust Tip Connection Clamp-On
Exhaust Tip Quantity Sold Separately
Exhaust Tip Shape Round
Exit Style Dual Out Rear
Finish Natural
Gasket Or Seal Included No
Grade Type Performance
Hangers Included Yes
Heat Shield Included No
Inlet Diameter 2.50
Inlet Type Weld-On
Main Piping Diameter 2.50
Mounting Bracket Included Yes
Muffler (Left) Body Height 5.00
Muffler (Left) Body Length 13.50
Muffler (Left) Body Width 10.00
Muffler (Left) Type Chambered
Muffler (Right) Body Height 5.00
Muffler (Right) Body Length 13.50
Muffler (Right) Body Width 10.00
Muffler (Right) Type Chambered
Muffler Body Height 5.00
Muffler Body Length 13.50
Muffler Body Material 409 Stainless Steel
Muffler Body Shape Oval
Muffler Body Width 10.00
Muffler Finish Black High-Temperature Paint Finish
Muffler Flanged Inlet No
Muffler Flanged Outlet No
Muffler Included Yes
Muffler Inlet Connection Slip-Fit
Muffler Inlet Inside Diameter 2.50
Muffler Inlet Outside Diameter 2.63
Muffler Outlet Connection Slip-Fit
Muffler Outlet Quantity 1
Muffler Part Number Kit Only
Muffler Quantity 2
Muffler Series Super 40 Series
Muffler Type Chambered
part type Exhaust System
Pipe Color Silver
Pipe Material 409 Stainless Steel
Product Type Exhaust System
Sound Level Aggressive
Spring Bolt Kit Included No
Sub Category Exhaust and Tail Pipes
Tail Pipe Outlet Outside Diameter 2.50
Tail Pipe Quantity Dual
Tail Pipe Tapered Outlet No
Type Crossmember-back
Valve Included No
Valve Type Not Applicable
Warning California Proposition 65
Packaging Information

Weight: 67.75 lbs
Dimensions: 59.75 x 16.25 x 15.25 IN

Safety

⚠ WARNING: This product can expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information visit www.P65Warnings.ca.gov

Warranty

View Warranty (PDF)

Installation Instructions

View Installation Instructions (PDF)

⚠ Fitment Notes
  • Aggressive sound; Super 40 Series Performance Mufflers; 2.50-inch Stainless Steel Pipes; Small Block Chevy Swap; Big Block Chevy Swap; LS Swap; LT Swap.
  • Fits 1968-1972 GM A-Bodies with V8 engine.

Vehicle Fitment

  • 1968-1969 Buick GS 350 Base
  • 1968-1969 Buick GS 400 Base
  • 1970-1972 Buick GS 455 Base
  • 1970 Buick GS 455 GSX
  • 1970-1972 Buick GS Base
  • 1970 Buick Skylark 350
  • 1972 Buick Skylark 350
  • 1968-1972 Buick Skylark Base
  • 1968-1972 Buick Skylark Custom
  • 1968-1969 Buick Special Base
  • 1968-1972 Buick Sportwagon Base
  • 1968-1969 Buick Sportwagon Custom
  • 1968 Chevrolet Chevelle 300
  • 1968-1969 Chevrolet Chevelle 300 Deluxe
  • 1970-1972 Chevrolet Chevelle Base
  • 1968-1972 Chevrolet Chevelle Concours
  • 1969-1972 Chevrolet Chevelle Concours Estate
  • 1969-1972 Chevrolet Chevelle Greenbrier
  • 1971-1972 Chevrolet Chevelle Heavy Chevy
  • 1968-1972 Chevrolet Chevelle Malibu
  • 1968-1972 Chevrolet Chevelle Nomad
  • 1968 Chevrolet Chevelle Nomad Custom
  • 1971-1972 Chevrolet Chevelle SS
  • 1968-1970 Chevrolet Chevelle SS 396
  • 1970 Chevrolet Chevelle SS 454
  • 1968-1972 Chevrolet El Camino Base
  • 1968-1972 Chevrolet El Camino Custom
  • 1968-1972 Chevrolet El Camino SS
  • 1970-1972 Chevrolet Monte Carlo Base
  • 1971-1972 GMC Sprint Base
  • 1972 GMC Sprint Custom
  • 1968-1971 Oldsmobile 442 Base
  • 1968-1972 Oldsmobile Cutlass Base
  • 1972 Oldsmobile Cutlass Cruiser
  • 1968 Oldsmobile Cutlass S
  • 1971-1972 Oldsmobile Cutlass S
  • 1968-1972 Oldsmobile Cutlass Supreme Base
  • 1968-1972 Oldsmobile F85 Base
  • 1968-1972 Oldsmobile Vista Cruiser Base
  • 1968-1969 Pontiac Beaumont Base
  • 1969-1972 Pontiac Grand Prix Base
  • 1968-1972 Pontiac GTO Base
  • 1970-1971 Pontiac GTO The Judge
  • 1968-1972 Pontiac LeMans Base
  • 1972 Pontiac LeMans Luxury
  • 1969-1970 Pontiac LeMans Safari
  • 1970-1972 Pontiac LeMans Sport
  • 1971 Pontiac LeMans T37
  • 1968-1970 Pontiac Tempest Base
  • 1968-1969 Pontiac Tempest Custom
  • 1970 Pontiac Tempest GT
  • 1968-1969 Pontiac Tempest Safari
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California Proposition 65 Warning

This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov ↗.