In FMU's words:
Take a look at our new rear section for the BMW E39 M5:
This system is made from 309 stainless steel and is fabricated by hand at Fluid MotorUnion in Plainfield, IL. The exhaust is installed by cutting the OEM rear section and replacing it with the FMU piece. Clamps will be included for an air-tight seal, and the FMU kit connects to all the OEM hangers for a perfect fit, just like OEM.
Instead of using mufflers, the FMU E39 M5 rear section uses one pass-through resonator for each tailpipe. With a typical muffler delete (thatís replaced by straight pipes), the resultant tone is raspy at best, and has a tendency to drone. The FMUís use of resonators in place of the mufflers allows the true sound of the S62 motor to stand out, with the end result being a deeper, more aggressive tone at heavy throttle loads while maintaining a great amount of civility during both start-up and idle.
This kit is a great idea for those looking for a cheaper alternative than a full exhaust kit, and also for those who are wary of deleting the catalytic converters. We also opted to keep the tailpipe design similar to OEM for that stealthier approach to exhaust modification. It doesnít have to look totally different to sound better. The retail version will come fully polished, as well.
Thereís also the added benefit of a bit of weight savings, as well. Take a look at the size of these OEM mufflers:
And now check out the FMU system in the same car:
Weíve also made a video featuring Mikeís M5, the willing donor for the first copy of the FMU rear section. Aside from the exhaust modification, his M5 is 100% bone stock. No trickery here. Minus the "weight reduction" in the corner of the front bumper from unfortunate contact with what was left of a deer on the highway. Enjoy the video, and let us know what you think:
Whenever youíre working on assembling several smaller pieces into one larger piece, being able to visualize the final result is important. Thatís why we lay out all the pieces for the axle-back exhaust in a row on the fabrication table. Or maybe it just makes for a good picture. Itís a mystery! ÖBut itís probably the latter of the two.
After everything is welded in place, we test-fit the exhaust system with the supplied clamps, in order to ensure a tight fit at all points, free of exhaust leaks or other pesky issues. We decided to use these specific clamps due to their smaller profile and their simplicity; rather than having to cut the OEM exhaust and weld on new flanges or v-band connections, this system lets you cut and then immediately clamp, saving you time and money during installation.