Originally Posted by TahoeM3
Andrew, it was argued by another tuner in a separate thread that the stock turbos are maxed out pretty easily and that the engine isn't capable of producing more power than what he had achieved with his tune...which is also far short of what Dinan claims (he also suggested that Dinan was fudging their numbers). I suggested that there might be an intake restriction and that with improved air flow that the engine could make more power. To me it seems to run out of breath. He pretty much dismissed my comments. What do you think? Could BMW have intentionally restricted intake air flow in order to limit power potential? Is it possible the intercooler is the bottleneck? Could either of those be improved to boost power?
By the way, I may well be completely wrong on this...I'm not saying I'm right. I'm just expressing my understanding of how turbo engines work. This is not meant to be confrontational or argumentative...it's just for purposes of discussion.
I have been looking at ALL
the available options right now and there are only 2 options for the really big numbers; Dinan and Hartge.
On the F10 550's Dinan are currently at stage 3 and the advertised numbers are north of 500hp now. There are a few guys who will be putting their stage 3 cars on the dyno in the coming days/weeks and I am awaiting those results. If they confirm the "claimed" Dinan numbers then I think this can be put to bed once and for all.
As far as the Hartge is concerned, their tune brings power up to 490hp which is comparable to Dinan. It appears that it is not a "flash" tune and more like a "piggyback". I contacted them directly, but unfortunately they do not offer engine tuning for U.S. cars. I will follow up with them to get more details on why they don't offer anything for U.S. customers.
Could these two companies be inflating their numbers for marketing? Very possible, but don't want to dismiss them so quickly. Until there is proof that these numbers are indeed "inflated" than I will reserve judgement.