(Responding to both UName and PT here...)
Focusing on physical/muscular speed only (as opposed to flightspeed), Black Adam has been clocked at much higher speeds than Thor (at least Mach 500). There really shouldn't be any dispute about that. However, I don't see him owning Thor on that basis. Superman is likely even faster than Adam, and has way more super-speed showings, yet his speed wasn't a game-changer against Thor in JLA/Avengers. I don't think that was because Thor has comparable speed, I think it was because Superman doesn't tend to use super-speed much during fights, and when he does, it's usually only in short bursts. If guys like Superman and Black Adam fought at super-speed all the time, they'd wreck Thor, but in practice, it's written as a occasional-use power that wouldn't be a deciding factor in most fights.
Do you mean running speed? We do have Thor described as running "faster than the eye can see" in JIM, which, if taken literally, would put him at possibly above that speed. Of course it is not an official measurement.