The X5 hasen't been getting much love with a lot of recent travel, other project wagons, a broken finger, and a new 2mo puppy but I do have some maintenance and mods collecting.
Fluidampr, fuel filter, oil filter, vac lines, and a 3" QTP e-cutout I had left over from a wagon project. I have also been researching and strategizing for a custom intake, a big intercooler retrofit, potential trans cooler, and tuners/exhaust for the deletes.

Buying well designed off the shelf items is great since you know fitment will be perfect but I do enjoy the challenge of a good DIY/retrofit project so I will likely end up retrofitting a VRSF race intercooler and building an RK Autowerk style cold air intake. I know the OEM system is well designed but if I play my cards right I should be able to build a system that has similar filtering properties and intake air temps while offering a shorter piping run. Plus more turbo noises and a unique intake system. Living in San Diego I don't have many worries about excessive water/dirt/etc. Climate is kind to cars out here.

For exhaust I like the ATM since it has an in-line resonator but they seem to be out of stock and have been for a while, if it's not available then VRSF DP with Rawtek mid pipe seems to be a nice setup and I like having the 2 bolt flange in place of the slip on design. Either way the plan is to put the QTP valve as far back as possible, ideally right before the OEM muffler. straight piped M57s aren't too loud but since this is a road trip vehicle it will be nice to have a "quiet" mode.

The Y-pipe supplied by QTP has pretty poor fit and finish with a lot of excess material protruding from the welds, this will need to be ground down to keep gasses moving smoothly. QTP also supplies a monster of a toggle switch that is hard to operate and looks like it should be installed in a aircraft from the 70s so I will be upgrading it to a more elegant/flush switch and try to integrate it around the headlight dial so it looks as OEM as possible.