As my age gets higher so does my ride height
Front KWs were raised to match the rear and ditch the rake for a level ride height, very happy with the the results. I am still developing thoughts on the KWs so for those interested in feedback please sit tight.
I am happy to report the exhaust system is complete. Installing the larger (wider) F85 rear differential meant the stock piping wouldn't fit and for the a while I ran some clamps, a resonator, and a turn down off my mid pipe which terminated just before the diff. I was toying with reinstalling my QTP exhaust valve as I appreciated having the option to open the valve when I wanted to puff my M57 chest but the reality is space was now a premium and although my QTP valve has been reliable, in general they are not known for being particularly so. I again, took the mature/classy/boring? route and decided to keep the exhaust quiet by skipping the valve, keeping the OEM muffler, and also adding a Vibrant Ultra Quiet Resonator.
I was surprised to learn the resonator killed a lot of the turbo spool. I run the same resonator on my E61 with twin turbos and the spool is loud and piercing, not on the M57 I guess those frequencies were gobbled up. The resonator also kept the hissing and fluttery noises to a minimum which I do appreciate as the growl of the M57 comes through better. Overall the sound of the system is subtle, a bit classier/cleaner, but still has character.
I had a local shop assist with the fabrication. They welded the Vibrant resonator into my Rawtek mid pipe, fabricated piping around the rear differential to connect mid pipe to OEM muffler, and fabricated piping from the muffler to accommodate the rear tips. A couple v bands were added to make the system modular and easier to install/remove.
Everything is mandrel bent and tig welded.
Here is the layout of the system:
Rawtek down-pipe
Rawtek catted mid-pipe w/ Vibrant ultra quiet resonator
OEM E70 X5D muffler w/ OEM F15 M Sport tips
Sorry for the shit pics but you get the idea...
Fitting F15 tips isn't for the faint of heart, it requires precise trimming and some creative fabrication skills to bring it all together. After mocking up the tips, eyeing, and measuring multiple times I was convinced it could work and proceeded to prep and trim the bumper. I traced the tip onto cardboard and then used a torx bit to extend the size, my goal was to have ~1/4" clearance around the tip, erroring on the side of "tight" and clearancing more as needed. Nothing is worse than having a hacked up bumper with excessively large holes. yuk
I applied tape to the bumper and used both the actual F15 tip and template to scribble my cut mark, double, triple, and quadruple checking as I went.
The driver side came out in about 20 pieces and I was a lot more proficient on the passenger side, here is the rough cut of the first pass, I came back in to clean up everything
Unibody was also slightly trimmed
Little OEM tip swimming in a sea of clearance.
Initial pics after installation.
Scratches on the bumper courtesy of the fabrication shop. Aside from this collateral damage I was very happy with their work. As you can see the bumper needed some additional clearance.
Added tape and revised my trimming.
Muffler/bumper fitment is so tight the bumper needs to be removed to remove muffler, not ideal but sometimes I sacrifice function for aesthetics, this is one of those times. V-band just before muffler makes this process much easier.
I thought about painting the muffler black to match the tips but it would have been a bit of work and I wasn't convinced it wouldn't chip over time from road debris so I decided just to refurbish the muffler and piping with some wet sanding, I love how you can bring new life to metal with some elbow grease.
Cleaned, scuffed, and primed.
....and painted
Final pics