I just wanted to share my experience with everybody. For my stubborn 2009 E90, it proved to be pretty challenging to iron out all the kinks in my tune. I'm just stage 1 with DCI running 93 Octane. The 4.01 Cobb OTS maps gave me more power but there were very noticeable timing pulls and boost oscillations. Acceleration was lumpy and there were hesitations and surges. Not BMW smooth at all.
I read a little about ATR and quickly realized it was way over my head. I might not be using the exact right terminology in the info below cause I'm not an expert but you'll all get the get the jist.
So it was time to contact the pro's at Protuning Freaks and I started working with Jake. Jake and I spoke on the phone twice and were emailing each other 1 or more times daily. He was great with staying in touch with me and quickly providing with almost daily map revisions.
My car proved very stubborn and Jake first tried the basics with playing with timing and load targets. By doing that, within a few days he got rid of the boost oscillations. He also found where the limit of how much boost and load my turbos were able to handle. So at this point we had more power no oscillations. Progress was being made.
The next step was the stubborn timing retardation and timing corrections. They were pretty bad and were very noticeable to me when driving and obviously showed up in the logs. We tried a bunch of different map revisions and were still struggling. Jake has contacts at Cobb and collaborated with Cobb and then we had a Eureka moment were some major revisions were done to the PID tables in a new map. Once this one done there were no more timing drops when doing full 3rd gear pulls! This was a great milestone and Jake never gave up and was very persistent.
I was still noticing some timing drops when doing hard down shifts on the highway where the boost and RPMS would rapidly shoot up. I sent these logs to Jake and bam, he made some more tweaks and got rid of those timing drops too. He even tweaked some things to help smooth things out under part throttle as well.
I guess everyone's car reacts differently to the OTS maps but if anyone out there has dirty Cobb logs and/or feels hesitations, oscillations, surges, etc. with the OTS map I'd highly recommend
www.protuningfreaks.com. We all spent almost a grand for the Accessport so another $200 for the e-tune is a no-brainer.
I have gobs of power now and power delivery is just as silky smooth as it was in stock tune. I couldn't be happier. If anyone has any specific questions for me feel free to pm me or reply to this post.