I understand that although this item is currently listed as in stock, inventory may change without notice and is confirmed once my order has been processed. I also understand that the item may ship as early as the same or next business day, but processing may take up to 7–10 business days in some cases, and all shipping estimates are subject to change.
I understand that this item ships directly from the manufacturer or distributor and that supplier inventory is not guaranteed until my order has been processed. I also understand that all lead times are estimates only, may change without notice, and are confirmed once the manufacturer processes my order.
I understand that this item is currently backordered and that any estimated availability or restock date is an estimate only, may change without notice, and cannot be guaranteed. I also understand that, depending on the manufacturer or supplier, some backordered items may be processed as Special Order items and, once processing has begun, may no longer be eligible for cancellation. If cancellation is permitted, it may be subject to applicable cancellation and/or restocking fees in accordance with the manufacturer's policies and our Terms & Conditions.
I understand that this is a Special Order item sourced or manufactured specifically for my order. I understand that all lead times are estimates only and may change without notice. Once my order has been processed with the manufacturer, it cannot be cancelled or modified in accordance with the Special Order Policy.
The IRL MaxFlow 400 Cell High-Flow Downpipes are engineered for enthusiasts looking to maximize the performance of their S58-powered BMW while maintaining a refined exhaust tone. Featuring premium 400-cell high-flow metallic catalytic converters, these downpipes provide significantly improved exhaust flow over the factory units, helping reduce backpressure, improve turbocharger efficiency, and deliver noticeable gains in horsepower, torque, and throttle response.
The IRL MaxFlow design promotes smooth exhaust flow to minimize turbulence and optimize performance throughout the entire RPM range. The result is quicker turbo spool, enhanced throttle response, and a deeper, more refined exhaust note without the harshness commonly associated with lower-cell-count catalytic converters.
Manufactured from premium T304 stainless steel and precision TIG welded, every set is built for exceptional durability and long-term reliability. Designed using OEM mounting locations, these downpipes provide a direct bolt-on installation and are compatible with both the factory exhaust system and most aftermarket cat-back exhausts.
Precision TIG welded for maximum strength and durability
Increased horsepower and torque
Improved turbo spool and throttle response
Reduced exhaust backpressure
Refined performance exhaust tone
Direct bolt-on installation
OEM-style fitment
Compatible with OEM and most aftermarket exhaust systems
Vehicle Fitment
BMW G87 M2 (S58)
BMW G80 M3
BMW G81 M3 Touring
BMW G82 M4 Coupe
BMW G83 M4 Convertible
Important Information: These 400-cell downpipes are not EPA certified and are intended for off-road and motorsport use only where permitted by law. While the 400-cell catalyst design significantly reduces the likelihood of a check engine light compared to lower-cell-count options, IRL does not offer a no check engine light (CEL) guarantee with these units. A CEL may still occur depending on vehicle software, fuel quality, driving conditions, and manufacturing tolerances. ECU tuning may be recommended to optimize performance and catalyst efficiency.
It is a violation of Federal and Illinois State laws to use this product in a manner inconsistent with it’s labeling. Our products are "Legal Only For Racing Vehicles Which May Never Be Used, Or Registered or Licensed For Use, Upon A Highway."
These products are designed for off road purposes only It is NOT designed or intended to be used in any way that may violate any laws. IRL LLC will not be responsible for the use of Merchandise.
We use cookies to improve your experience on our website. Read about how we use cookies in our Privacy Policy. By browsing this website, you agree to our use of cookies.
privacy policy
