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Supplier details checked 2026-09-23 · Test catalog
1968-1970 Mopar B-bodies with V8 engine, 2.5" Stainless Steel - Aggressive to moderate sound
Flowmaster American Thunder Crossmember-Back Exhaust System
Does Not Include Header Reducers or Downpipes for Factory Manifolds
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 reducer cones or downpipes for factor manifolds.
Flowmaster 68-70 Mopar B-BODY 2.50in. American Thunder SS Exhaust System
6870 MOPAR BBODY 250 AMT 409S
SYS 68-70 MOPAR B-BO
The American Thunder system is for the person who is looking for a complete Crossmember-Back dual exhaust system with a deep powerful sound. The system is constructed from 2.50-inch mandrel-bent stainless steel tubing and includes an H-pipe to balance the exhaust pulses and to eliminate back-rap on deceleration. The large cased Super 40 Series performance mufflers generally deliver a moderate interior tone with a deep powerful exterior sound which is suited for enthusiasts who want their performance to be heard. The mandrel-bent tailpipes exit straight out the back under the rear bumper for a strong muscular appearance and allows you to select your own style of tips. Designed for an easy fit, these systems include all necessary parts and hardware for easy installation and is covered by our Lifetime Limited Warranty. .
SYS 68-70 MO
