Originally Posted by JimD
It's all guessing but the dyno runs of the guy who put the 3 stage on but didn't re-tune suggest to me that the 3 stage inlet is not a magic bullet
You are correct, the untuned 3 stage DISA is not a silver bullet, but it makes a noticeable change in character even without any tune. Based on other peoples dyno's, I predict without a tune that the gain is up to a maximum 10 hp and 15 tq.
I noticed that my rears broke traction more, the power surge or bump after 3.5k prm feels great, the RPM climb quicker & aggressive after 3.5k. My father who didnt drive the car for about a week noticed too on the first drive, I don't think it was the high of a successful DIY as we kept quiet for most of the drive to stay unbiased and analyze. A few days later I noticed the low end torqe boost in traffic and parking lot situations. I'm very satisfied and as a result reluctant to jump to just any tune, especially since I know what European tuners can do.
I must admit that both Evolve and Eurocharged have been great at answering questions in detail, and AA tune has a great FAQ thread. Other tuners (mostly those that tune m3's) have responded to claim 15hp gain, but have yet to show dyno's or inspire confidence in their n52 products. I guess we are just not their market of focus.