7-zip doesn't preserve the Linux/Unix owner/group of files and possibly other details. Use tar instead because it's designed to preserve these things, then just 7zip the tar archive.
tar cf - --exclude=\*.o -v directory | 7z a -si -t7z -m0=lzma -mx=9 -mfb=64 -md=32m -ms=on directory.tar.7z