Always a good question but I don't think they can been narrowed down to the exact proper scale as even though a particular train may have its height to scale, its length is certainly not. Check out this older thread where we discuss your very question...
http://www.blueplastictracks.com/showthr...ight=scale
http://www.blueplastictracks.com/showthr...ight=scale
![[Image: 7071.gif]](https://www.allsmileys.com/files/sweetim-texticons/7071.gif)