I'd get a dyno and check your A/F ratios sometime to be sure that you haven't screwed things up too much. What you've done is this:
Putting the bend in means that most of the air will take the path of least resistance, meaning the outside of the bend (which is the part of the flow sampled by the MAF) will carry most of the flow. This is how what you have done has brought the intake velocity up sufficiently for the MAF to read it.
This means that you have changed the SHAPE of the velocity profile of the flow that goes past the MAF, in addition to adjusting the magnitude by using the larger housing. If the velocity profile changes, the MAF transfer function will need to be adjusted.
The dynamic trim adjustment based on the o2 sensor in our car can compensate for changes in magnitude, but not for changes in shape, so I worry that you might have thrown some of the A/F ratios off by doing this.
This of course, assumes that the stock intake was straight, which it may not have been, I know in the regular 3, the intake had a bend in it right before the MAF as well, so you may have simply been returning the velocity profile back to its original shape, check your stock intake, and see if there is a similar bend right before the MAF (I don't have a speed 3, so I can't speak to this).
You're probably fine. As others will tell you, I'm a paranoid freak when it comes to my car, as long as it appears to be running fine, you should be ok, just make sure it doesn't go lean at all at higher rpms+load, b/c that will cause detonation, which is a very bad thing, especially on a turbo car.