From my personal memory, these are the numbers I seem to recall:
Intamin:
Rails are 6" in diameter
Track width is 2.5 feet, from rail to rail.
B&M:
Rails are also 6" in diameter,
but track width is 3 feet from rail to rail.
Don't forget, however, that the depth of the track varies, regardless of it's shape. For example, the box beams B&M use can grow taller or shorter depending on the design needed for that section of track. Intamin also does this with their box track, however, I do not know the measurements and so have to just leave you with that.
*** Edited 11/18/2006 9:20:16 PM UTC by Jesmcsel***
Jes
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