[BavarianMotorWorks]

Hey guys so I recently installed the Cobb tune on my 2008 135i 6mt a few days ago and I have some questions and concerns. Also keep in mind I am completely stock except for the tune. Well at least in terms of performance mods.

So first the good. Install was quick and took about 18 min without any errors. I've tried pretty much all the maps and I won't get into detail about it since there is a huge thread about it already and I agree with pretty much everyone else on them. Just to let everyone know I prefer 2.01 maps. The car for the most part feels pretty good. I tried 91 oct maps first just to be on the safe side and everything felt great. I decided then to try 93 oct maps and it did make a pretty significant difference. I've been on 93 maps for the past few days I've had the Cobb installed. 2nd gear is completely useless if I go WOT and 3rd gear now pulls a tad bit harder vs 2nd gear stock. All my testing was done in 70 degree weather.

Now for some questions/concerns.

I think this has been discussed before but I have one code detected on my Cobb that will not erase. I think it's that "missing code" one that everyone is talking about. Can someone just confirm that this is normal and would go away if Cobb is un-installed.

Another concern is how well other people's stock clutches are holding up. I have 21k miles on my car and have never launched or have done many powershifts before on my car. My concern is that I was on 2.01 maps (which by the way builds a lot of boost even at 20-30% throttle) and was in 6th gear at maybe 2k rpms. I pressed the gas in to about 20-30% and it boosted over 10psi very quickly. I noticed and felt this sort of vibrating sound coming from underneath the car. It almost feels like my clutch is slipping even though the car is still accelerating. Now I would never go WOT in 6th gear starting at 2k rpms but as people have said 2.01 maps might boost at WOT levels even when pressing in the pedal 50%. So in that moment I might have close to those boost levels. Has anyone else noticed this in 6th gear or any gear for the matter such as 4th?

Also I feel the time it takes from going WOT and building max boost is increased. Basically I'll go WOT and immediately I'll feel the car start to pull but only at a fraction of the power and then like half a second later full boost kicks in hard and I'm off. This sequence happened even when I was stock but happened a tad bit quicker. Obviously it should take longer since I'm now waiting to built nearly double stock boost levels so just wondering if this is normal and if other people have noticed the same thing.

And lastly this is with the DV. I think I know where the surge is coming from when using 2.00 maps. Once thing I noticed with the 2.00 maps is when you go aggressive on the throttle and then release suddenly you don't hear the DV that much. Instead it almost seems like the boost is circulated back smoothly resulting in that surge everyone gets where it still feels like you're accelerating. Now in the 2.01 maps and 2.02 maps the surge is gone BUT you hear the DV much more distinctly now. Meaning if I go aggressive on the throttle and let go abruptly just like before you'll get the slightly lurch forward feeling before the DV circulates the boost back and you hear the air going through very distinctly also whereas in the 2.00 maps you hardly every heard that sound. So I think in the latter maps something must have changed with regards to how the DV is working. Anyone else can confirm this?

And lastly I did a few logs and I have no idea yet how to graph it. I'm hoping someone can graph it really quickly and see if anything is off. And we'll have more data on how the Cobb tune is running on a completely stock car. I have 3 logs and all were done just in 3rd gear to about 5-6k. Sorry I didn't have enough road to take it into 4th. Temps were 70 degrees and all were done on the same day within 30 min of each other. Keep in mind I was playing around with the Cobb so there's prob some useless data in each of the logs so look for the part where I start at around 3k and go WOT and let go around 5-6k.

You can find my logs here:

https://public.me.com/davidjbak

-Dave