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Header-back System 409S - Dual Side Exit - American Thunder - Aggressive Sound | 37A817412
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Flowmaster

Header-back System 409S - Dual Side Exit - American Thunder - Aggressive Sound | 37A817412

Part #37A817412
$1,160.53

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This American Thunder® exhaust system comes as a complete true dual crossmember-back exhaust for your 1964-1967 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 a moderate to 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 the rear corners of the car and 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
  • Moderate to Aggressive Exterior Exhaust Tone
  • Crossmember-back True Dual Exhaust System
  • Lifetime Limited Warranty
  • Mandrel bent 16 gauge stainless steel tubing
  • Aggressive Sound Exterior Exhaust Tone
  • Includes hangers and hardware for easy installation
  • Header-back System
BrandFlowmaster
Product Dimensions 53.34 x 29.21 x 127.64 inches
Manufacturer Part Number817412

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  • Ship-to-store items: Ready in-store in 1 to 4 days.
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Most unopened online purchases can be returned or exchanged at any of our store locations within a year from the date of sale. Some exceptions apply. See our return policy for full details.

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