I found an interesting point of reference offered by Mark Williams:
http://www.markwilliams.com/braketech.aspx

Rule of thumb from their website:
9.6 sq in = 7/8 MC
14.4 sq in = 1" MC
19.2 sq in = 1 1/8 MC

-'02 Dodge Viper Ex-World Challenge racecar
-'73 Duster, 6.1 based 392 hilborn hemi, tko600, full floater rear 9", Hellwig custom bars, viper brakes, built for road course