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Supplier details checked 2026-09-23 · Test catalog
Fits 1964-1967 GM A-Body with V8 engine, 2.5" Stainless Steel Pipes. - Aggressive to moderate 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 Stainless Steel Tubing
Moderate to Aggressive Exterior Exhaust Tone
Crossmember-Back True Dual Exhaust System
Lifetime Limited Warranty
Does Not Include Header Reducers or downpipes for factory manifolds
Flowmaster 64-67 GM A-BODY 2.5 in. American Thunder SS Exhaust System
6467 GM ABODY 25 IN AMT DOR 409S
SYS 64-67 GM A-BODY
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.
SYS 64-67 GM
