I can see you have recently found that:
http://chdk.setepontos.com/index.php?topic=8715.0At the moment you have no luck - there's no CHDK for sx160 yet. And I can't see any significant progress on this forum thread... You can either try to port it by yourself or find somebody who own this camera and has time/skills to make the port...
EDIT:
In case you want to ask: "will CHDK for sx150 work? Or other?" This is very very unlikely. It never happened before that CHDK for one camera model can run on other one without any modification of the source...
PS. Don't ask the same question multiple times...