MAD BMW G8x S58 3.5" Fat Boy Downpipes M3 M4 crank hub The two piece bushing design

The two piece bushing design sandwiches the subframe locking it in place

No additional hardware is needed

4-ply silicone couplers as well as stainless steel t-bolt clamps

Direct stock replacement

Flex-Fuel Feature - The ability to adjust the Engine Computer parameters on the fly

MAD BMW G8x S58 3.5" Fat Boy Downpipes M3 M4 crank hub The two piece bushing designOUT OF STOCK May 2nd 2023 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