Flow-focused exhaust path
Large-diameter tubing, smooth bends, and a flex section reduce restriction versus the factory exhaust path.
Large-diameter tubing, smooth bends, and a flex section reduce restriction versus the factory exhaust path.
Catless setup. Review local emissions requirements and product notes before street use.
Designed to retain OEM-style fitment without cutting or welding on supported applications.
Downpipes can affect emissions readiness, sound level, and calibration needs. Review the product description before ordering.
The MAD 3.5" S58 Fat boy is the largest BMW S58 catless downpipe on the market!
Upgrade from the stock S58 downpipes to the MAD 3.5" Fat Boy S58 catless downpipes for maximum airflow, power, and sound!
Upgrade to the MAD BMW 3.5" Fat Boy S58 downpipes to eliminate the backpressure caused by your stock catalytic converters. By upgrading to our downpipes, your turbos can now spool faster and achieve maximum power. As a bonus, your car will sound a lot nicer as well.
Expect up to a 30HP increase on a tuned BMW S58 with stock turbos, even more on cars with upgraded turbos.
The flex pipe Section will help reduce the stress and unwanted vibration from the downpipes.
Features:
Fitment:
SKU:
MAD-047
Emissions Disclaimer:
This product is not legal for sale or use on pollution-controlled vehicles operated on public roads, highways, or streets. It is intended for off-road, race, or closed-course competition use only, where such modifications are permitted.
By purchasing this product, you acknowledge and agree that:
You are responsible for compliance with all applicable emissions laws and regulations.
MAD and its affiliates disclaim any liability for improper or unlawful use of this product.
Use of this part on public roads may violate the Federal Clean Air Act (42 U.S.C. § 7522) and similar state laws.
Please check your local laws before purchase and installation.
Built for supported BMW S58 applications. Check the product description for G80/G81 M3, G82/G83 M4, and G87 M2 coverage before ordering.
Confirm supporting hardware and calibration requirements before installation.
Orders ship with tracked delivery and insurance coverage options at checkout.
Unopened items may be returned inside the stated return window per policy terms.
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