Flowmaster American Thunder Cat-Back
Fits 2015-2020 2.7L EcoBoost · 3.5L EcoBoost
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Price tracked 15 times since Jul 12, 2026 at the stores we check daily, not eBay: low $1,014.26, high $1,171.95, currently $1,171.95.
where to buy · 4 retailers tracked
A cat-back exhaust replaces the piping and muffler from the catalytic converter back. Flowmaster's American Thunder line uses their classic chambered-muffler design, known for a deep, old-school American V8-style rumble.
why this one — American Thunder is Flowmaster's classic, moderately aggressive tone - a middle-ground pick if you want the recognizable deep Flowmaster sound without going as loud as their Outlaw line.
No manufacturer or independent dyno figure found for this specific product. Cat-backs on turbo trucks with a downpipe/tune doing the real work typically carry no standalone gain claim; sound/tone is the primary value prop.
Estimated from comparable claims: MBRP ~+5 whp; Corsa +12; Flowmaster 11; Flowmaster 18
Questions about this category
No published gain figure for this part, and nothing here is a guarantee. Price is a list price and can lag the retailer; confirm at checkout. See how we check a price and our affiliate disclosure.