Description
Overview
The Flowmaster American Thunder Crossmember-Back Exhaust System is a true dual, large 3.00-inch muscle car exhaust built for the enthusiast chasing a deep, aggressive sound from a high horsepower vehicle. Engineered as part of Flowmaster’s American Thunder series, this complete crossmember-back system replaces the restrictive factory piping from the crossmember rearward, letting your engine breathe and your presence be heard from both inside and outside the cabin.
Every tube in this system is mandrel-bent stainless steel for maximum performance, preserving full diameter through each bend so exhaust flow stays strong and unrestricted. An integrated H-pipe crossover balances exhaust pressures between the two banks, helping to add horsepower and torque while reducing back-rap on deceleration for a cleaner, more refined tone under throttle-off conditions.
Sound & Performance
At the heart of the system are specially selected Super 40 Series performance mufflers. Their large case design is built to handle added horsepower while delivering the deep, muscular tone the American Thunder line is known for. That sound flows out through large 3.00-inch tailpipes, producing an aggressive interior and exterior character that grows with your build. As with any performance exhaust, the exact sound level depends heavily on your engine and level of modifications, so higher-output combinations tend to reward you with an even bolder note.
Key Benefits
- True dual 3.00-inch mandrel-bent stainless steel construction for maximum flow and durability
- H-pipe crossover balances exhaust pressures to add horsepower and torque and help eliminate deceleration back-rap
- Super 40 Series large-case mufflers deliver a deep, aggressive muscular tone
- Improved throttle response, power, and mileage — hallmark Flowmaster benefits
- Includes all necessary parts and hardware for a straightforward, designed-for-fit installation
- CARB (California) compliant with a Silver pipe finish for a clean, understated look under the vehicle
Configuration & What’s Included
This crossmember-back system comes with the Super 40 Series mufflers included and all the parts and hardware needed to get it installed. Exhaust tips are sold separately, giving you the freedom to finish the look exactly how you want. Note that a heat shield is not included with this system. Designed for 2WD applications, the American Thunder setup is a purpose-built upgrade for the driver who wants both measurable gains and an unmistakable soundtrack.
Fitment & Warranty
Built for 2WD vehicles and engineered for an easy, direct fit, this American Thunder system is backed by Flowmaster’s Lifetime Limited Warranty. Please note this product carries a California Proposition 65 warning. Choose the American Thunder Crossmember-Back system when you want serious flow, a deep aggressive tone, and the confidence of proven Flowmaster engineering.
