Bună!
Vezi nişte tutoriale la linkul :
http://www.ibtimes.co.uk/......rbread.htm
http://www.hotspotshield.co/2013/07/downgrade-galaxy-ace-2-gt-i8160-to.html
http://www.ibnewsline.com/......breadguide
http://www.droidviews.com/......oid-4-1-2/
Toate cele bune.