Watch your ibus anything over 10 will slow lacto growth. I used a starter with wyeast lacto 24 hours at 90f then pitched sac at 72 and let it finish. It took another 3 months to get moderately sour. Try getting the lacto pitch 5x larger and let it sit warm for a couple of days and it should be pretty sour.
Also, you should do a search on the Burgundian Babblebelt hombrew forum and you will get tons of info on brewing a berlinner weisse. Ultimately you will have to choose your own path, but it will give yo ulots to think about!
