MAD BMW G8x S58 3.5" Fat Boy Downpipes M3 M4

Looking to upgrade your BMW S58's performance? The MAD 3.5" S58 Fat Boy Downpipes are the largest catless downpipes available in the market today. Our downpipes offer maximum airflow, power, and sound, making them the...
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SKU: MAD-4047

Category: All Product, Downpipes


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Orders ship within 2 to 5 business days.

Looking to upgrade your BMW S58's performance? The MAD 3.5" S58 Fat Boy Downpipes are the largest catless downpipes available in the market today. Our downpipes offer maximum airflow, power, and sound, making them the perfect upgrade for your stock S58 downpipes. By eliminating the backpressure caused by your stock catalytic converters, our downpipes allow your turbos to spool faster and achieve maximum power. You'll notice a significant improvement in your car's performance, as well as a nicer sound.

Our downpipes are designed to provide up to a 30HP increase on a tuned BMW S58 with stock turbos, with even more power on cars with upgraded turbos. The flex pipe section of our downpipes helps reduce stress and unwanted vibration, providing a smoother driving experience. With the MAD 3.5" Fat Boy Downpipes, you can expect improved acceleration, faster spooling, and a better overall driving experience.

Upgrade your BMW S58 with the ultimate performance upgrade - the MAD 3.5" Fat Boy Downpipes. Our downpipes are crafted with precision and care, ensuring that they fit seamlessly into your BMW S58's exhaust system. Order now and experience the full potential of your BMW S58!


Compatible with right-hand drive and left-hand drive vehicles
Smooth bends for maximum airflow without any drone
Up to 30HP increase on the stock turbos, even more on upgraded turbos
Lifetime warranty on defects and fitment
90 day return period
All orders ship in 1-2 business days
Spot on fitment
Flex section

2021+ BMW M3 G80
2021+ BMW M4 G82 G83


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Return or exchange any item with original purchase receipt within 30 days as NEW requires that item must be in original condition and packaging, unopened and uninstalled, including all original materials supplied with the item. Returns that do not meet these criteria will be denied. Items returned for warranty may be exchanged or refunded or credited at our discretion. Credit will be issued to the same card used for purchase.

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The list below provides a high-level list of merchandise that is classified as non-returnable per our Return Policy.Some parts may be denied return because they share the same categorization as their electrical counterparts denial and process the return. This list represents most but not necessarily all of the non-returnable parts; - Including but not limited to MHD & BM3 Licenses , Custom Software Calibration files , SALE items. Also please review the manufacturer return policy before your purchase.

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MAD BMW G8x S58 3.5" Fat Boy Downpipes M3 M4
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