MAD BMW B58 2025+ Gen 3 M340 M440 Fat Boy 5.0" Downpipe Catless
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Upgrade your 2025+ BMW M340 M440 with the MAD BMW B58 Gen 3 "Fat Boy" 5.0" Catless Downpipe—the ultimate performance upgrade designed to unleash the full potential of your engine. Crafted from premium-quality 304 stainless steel, this larger-diameter 5.0-inch downpipe offers superior airflow, delivering enhanced horsepower, quicker turbo response, and noticeable torque gains.
The increased diameter of the "Fat Boy" downpipe sets it apart from our standard catless models by providing a deeper, richer, and significantly more aggressive exhaust tone. Precision-engineered welds and exceptional craftsmanship ensure perfect fitment, durability, and peak performance for enthusiasts demanding maximum results.
Transform your BMW M340's driving experience by choosing MAD's top-tier downpipe, designed specifically for drivers seeking ultimate airflow and a sound profile that commands attention.
Features:
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Premium 304 stainless steel for superior durability
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Expanded 5.0-inch diameter for unmatched airflow and performance
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Deeper, richer, and more aggressive exhaust tone
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Improved horsepower and torque compared to standard catless downpipes
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Precision craftsmanship and perfect bolt-on fitment
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Ideal for high-performance builds and enthusiasts seeking maximum results
- 2025+ BMW M340
- 2025+ BMW M440

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