Sounds like he's marking his territory not really peeing. My dog does the same thing. We've tried for 6 years to get him to stop. I'll be watching this thread closely to see if anyone can help. I'm pretty sure all the suggestions will be things we've tried a hundred times.

First.......is he neutered? If not, then neutering will help solve the problem.
When you take him out at 8pm do you go to bed shortly after? If you're staying up until later, then you should take him out again right before you go to bed.
My dog could never go as long as your dog goes between pee breaks. He can 'hold it' if he has to, but if we're home he asks to go out about every 2 hours.

Since you're asleep when he's peeing, you'll never catch him in the act. Soooo, he needs to be isolated somehow. If you don't want to crate him, then try a collapsible pen. Remove any water early in the evening (after he's eaten), take him for a walk before bedtime and then place him in the pen when you go to bed. He'll be more comfortable thru the night and he'll learn he can no longer roam at will.

Is your dog fixed???

Our pekingese was neutered and still peed all over the carpet until he was almost 2. We've had dogs before and none took as long to housebreak. Maybe because we got him in January and the weather was bad he would just hunker down outside and cry but didn't get the idea he was supposed to pee. I kept taking him out and finally he figured out what to do, he's 2 1/2 now, lets me know when he has to go out.