Again, never disputed the dyno numbers, and the stock filter is definitely a bit restrictive. Not sure why you think I'm disputing the dyno numbers. Just pointing out that dyno numbers don't translate 1:1 to real world experiences. For 99.99% of people, a 10-15 HP increase might as well be zero. That dyno is also a bit suspect. Stock F10 N55 only making 240hp? Something's broke.
Stop spouting nonsense about "but BMW could have if they wanted to!" You're missing the scale of things here. They sell tens of thousands of 5ers a year. When you're a major car manufacturer that is trying to maintain certain reliability standards and more importantly, emissions standards, a 50HP bump is not an insignificant number. Is a stage 1 significantly less reliable? Absolutely not, and most people won't run into reliability issues. But will it objectively reduce reliability in the grand scheme of things? Yep. And when scaled, even a 1% reliability decrease can cost you a lot of money.
A ram style intake isn't about restriction, it's about reducing the length of tubing between the intake and the turbo inlet. Less volume, less inertia to overcome, better throttle response. And while we're talking about physics, let's do some math here.
Using
this calculator, we can see that at redline our engines consume about 741 CFM of air. Our intake tubing is 3.5" or so. Using
this calculator, assuming we're traveling at 60mph (5280 feet per minute), our stock plumbing can take in close to 1411 CFM of air, almost double of what our car needs at redline. So obviously, plumbing is not the restriction here. Next, we need to look at the CFM of our filters. Good quality paper filters flow about 4.95 CFM per square inch. Given 741 CFM required, we need about 150 square inches of filtering capacity. Our stock filters are 112 square inches. Not great, but not bad either. More airflow is not just more airflow, your engine only needs a certain amount of it. Below 5000 RPM, our stock filter is actually fine. If you really want to get that last 2k RPM restriction out, using a drop in filter is actually just as good as the Air Charger. Which is probably why most people use the drop in filter.
Lie about their power figures? Lolwhut? Lying requires the intent to deceive. BMW underrates their cars, that is not the same as lying about their power figures.
...what? Air to water? Are you confusing intercoolers with intakes here? They're both DI yes, but do you not understand that the intake plumbing is VASTLY different between the two cars? I believe he used a Forester in the video. Take a look at the forester's intake design. Heck, the filters aren't even the same size as our car's. Trying to extrapolate information from an entirely different design is misleading at best.