ok so to start, i have recently purchased a 2002 b5 s4 with a tip( i know ) back injury limits use of left leg for the time being. anyway on to the goods. i have an AA box and have done tons of reading. i belive i have everything figured out and ready to start tuning using me7 ecu flasher and tuner pro. i would love to be able to someday decode my AA box but it apears if i use a L box bin file (which i have) and an M box definition file (xdf) i should be able to tune said L.bin using M.xdf and flash over my AAbox... sorry if this is getting long winded i just dont want to go effing up without a definitive answer as to the safety and weather or not there are any details i need to ensure before going forward. ie the origin of my bins and xdfs are all from here and after trial and error ive found a pair of files wich play well and have every definition im looking for for my first relaxed stage 1 tune( all stock at the moment). i appreciat any help you guys can offer and im looking forward to any links or info you can throw at me. im definetly not affraid to do the work to decipher my answers but a bit stumped at the moment with where else to look. thanks in advance. HAPPY TUNING everyone.

Thanks for the reply! I believe after correcting the checksum I am ready to try my new base tune. By the way I'm in mpressed with your ability and knowledge here. I see your name all over every forum.