Convert avi to flv with best quality

Hello there,

I've a video avi with very high quality. I've tried many different settings, but still loose quality while converting avi to flv.
Video is 800x600. Could you please help me with settings?
I would like to have best possible quality, no limits for brandwith or file size.

My settings now are:
ffmpeg -i 'movie.avi' -g 600 -qmax 10 -r 25 -y 'result.flv'