I am interested in this, use the correct maps exclusive for the 335iS recommended by others and see if your still getting slippage, and then try Cobb by itself and see if you get slippage.
Do not try brake boosting. Stay away from it on this particular car. If you are getting slippage on the JB tune and not on the Cobb, then my theory is correct:
Originally Posted by BuraQ
The DME reports to the DCT values that calculate how much pressure to apply to the clutches to avoid slippage from "increased HP" ie, boost, target, throttle position etc. This will be problematic for piggyback users ie clutch slippage should be more expected on such tuning platform
If your DME "thinks" the turbos are producing only 12 PSI the DCT calculates that into an aproximate HP value and then ups the bar pressure to 10 when in fact you are running more PSI and more HP, which causes the clutches to slip then leading to more heat which will lead to more slip.
Also brake Boosting is harmful to your DCT and will cause slippage if used too many times especially with a piggyback setup on the DCT 335iS exclusively
FYI, I am nearing 200+ launches using LC and my DCT is still STRONG, no slippage whatsoever