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Supplier details checked 2026-09-23 · Test catalog
Fits 1964-1967 GM A-Body with a V8 engine. 3.0" aluminized pipes - Aggressive sound
Flowmaster American Thunder Crossmember-Back Exhaust System
H-pipe Crossover for Maximum Power and Deep Tone
Super 40 Series Mufflers for Deep Powerful Sound
Includes Hangers and Hardware for Installation
Mandrel-bent 16-gauge Aluminized Steel Tubing
Crossmember-Back True Dual Exhaust System
Aggressive Exterior Exhaust Tone
True Dual 3.00-inch Exhaust
Does Not Include Header Reducers or Downpipes for Factory Manifolds
Flowmaster 64-67 GM A-BODY V8 3in. American Thunder Crossmember-Back Exhaust System
6467 GM ABODY V8 3 AMT
SYS 64-67 GM A-BODY
This American Thunder® Crossmember-Back exhaust system is a true dual 3.00-inch muscle car system that gives your car a deep aggressive sound. This aluminized steel system is mandrel-bent for maximum exhaust flow and performance. The system includes an H-pipe crossover to balance out the exhaust pressures, add hp and torque, and to help eliminate back-rap on deceleration. The specially selected Super 40® Series performance mufflers are in a large case to handle the high horsepower and provide a deep muscular tone while flowing through the large 3.00-inch tailpipes. The American Thunder systems generally deliver an aggressive interior and exterior tone and are suited to the enthusiast who wants their performance to be heard. The sound level will depend greatly on the engine and level of modification. 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. Covered by our 3 Year Limited Warranty.
SYS 64-67 GM
