Diamond Eye Performance 4"/3.5" Cat-Back System
Fits 2011-2014 3.5L EcoBoost
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Price tracked 13 times since Jul 12, 2026 across the stores we check daily: low $440, high $574.99, currently $440.
Diamond Eye's 4-inch/3.5-inch cat-back system for 2011-2014 trucks.
why this one — The listing states this isn't CARB-legal - if you're in California or another CARB state, run this by an attorney or check your local emissions rules before buying.
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
Listing states not CARB-legal.
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.