I was able to get the X5 on some dynos, both a Mustang Dyno and a Dynojet.

Mustang was 317whp 504wtq
Dynojet was 370whp 520wtq

For those that don't know Mustang dynos use load and typically read lower. In general Mustang dynos should be more accurate but it's hard to say since it all comes down to proper calibration. Dynojets are more common for "big stick" comparisons amongst enthusiasts as dynojets are simply and measure power based off how quickly the vehicle can spin a drum, less variables to manipulate the numbers.

The dynojet operator was starting the pulls at way higher RPMs then he should have, shame on me for not picking up on this but he was going WOT between 2,500 and 3,000 rpm (seriously) and the M57 makes peak TQ around 2,950 so for my observant BMW diesel enthusiasts you may notice the Dynojet TQ numbers seem low, this is why, with a clean pull TQ #s would likely be ~550wtq.

On the Mustang dyno I was able to compare my custom inlet to the OEM airbox and although the data isn't perfect since the engine was getting a little heat soaked, it looks like the intake does flow better and offered more power, roughly +10hp +10tq. I am patiently waiting for the shop to email me the overlaid graphs.

On the Dynojet I did 2 pulls with my custom intake and 2 with just a 3.5" velocity stack mounted on the MAF. The pulls are so chaotic and the data so sloppy it's hard to discern what's going on but there was no measurable difference between the two.

Mustang session


Dynojet session


Custom Intake


Velocity stack