mpeg1 bitrate and filesize

[baddreams]

Can someone please tell me why no matter what the bitrate is, the filesize is always the same?

I'm using tmpgenc to encode a 2min clip into a mpeg1 file at various bitrates (200,500, 1150) but the filesize is always the same!

[Treebeard]

if you change the bitrate you also need to change it to Video CD(non-standard) on the last tab under settings. this will fix that file size problem; although i dont understand why you would lower it that far, quality will really suffer.