Ok, time is not scalable, it's a constant, right?
So if a 1/1 car covers one mile in 60 seconds, it's traveling at 60 mph (a mile every minute).
If a 1/25 car covers a "scale" mile (1/25th of a mile) in the same 60 seconds, it's covering 1/25 of a mile every minute, or a full mile in 25 minutes. So 60 mph in 1/25 scale is 2.4 mph?
Right?
Edit: Didn't see Junkman's post... he already covered it.