PROFILE

The ARM S58 4.5" Single Midpipe upgrade is designed to unleash the incredible exhaust sounds from your G8X M3/M4. By removing the secondary catalysts and two middle resonators, the ARM S58 Midpipe substantially improve the sound of your S58 powered BMW.  Also, by retaining the OEM muffler, you still have the ability to control the exhaust valves, allowing you to close them for a more subtle tone for when you want to be quiet, or open the valves for maximum sound.

ENHANCE THE SOUND OF YOUR S58

CONSTRUCTION

The ARM S58 Midpipe is a 4.5" designfrom the downpipe connection all the way to the rear section where it will reduce to 2.75" to perfectly connect to the OEM muffler section.  The ARM S58 Midpipe start with a OEM-style 2-Bolt flangewhich can mate up to either the OEM downpipes, or upgraded downpipes that fit the OEM exhaust.  These flanges will accommodate the OEM midpipe gasket perfectly. 

The ARM S58 Midpipes then transition to the 4.5" Midpipe section of the exhaust via the slip-fit connections.  Where the exhaust merges is the heart of the ARM S58 Midpipe where you have the 4.5" Midpipe and this is where the magic happens.  The sound waves of each bank of your S58 engine are combined to produce a much more exotic and richer exhaust note.

From the Single 4.5" Midpipe the ARM S58 Midpipe transitions back to the OEM muffler, which allows full use of the OEM exhaust valves.  This gives you the freedom to choose between open and closed exhaust flaps, controlling the volume your G80 M3/M4 produces.  Upgrade the look of your G8X to match the sound of your ARM S58 Midpipe by completing the kit with a set of ARM S58 Exhaust Tips. 

The ARM S58 Midpipe will secure to the exhaust hanger on the passenger's side using the OEM style mounting bracket. This helps the exhaust from jostling around during aggressive driving.

AXLE BACK ADAPTERS

The ARM S58 Axle Back Adapters are designed to reduce down at the end of the midpipe to fit most aftermarket axle back systems. Most aftermarket axle back systems reduce down from 3" (76mm) to 2.75" (70mm) and that's where the ARM S58 Axle Back Adapters come in.

IN THE BOX

• 2x ARM Downpipe Gaskets
• 1x ARM Extended Brace
• 2x Front 4.5" Midpipe Sections
• 2x Rear Exhaust Sections
• 5x ARM Clamps

FITMENT GUIDE

 The ARM S58 H-Pipe and X-Pipe Midpipes fit the OEM center exit exhaust.