Posting a timeframe of 8 hours isn't helpful at all, unless a piece of your brain is missing, you know that uploading at 3am isn't wise.
The timeframe is something you'll have to figure out on your own, because everyone's viewing habit is different. I used to post at about 12pm PST because kids on the East Coast would be getting out of school, but many times that bombed for whatever reason. I'm going to have to go through this trial and error myself again.