BL setup questions emaxx 3905

[jediguru]

So I'm looking to convert my new emaxx 3905 to a single motor BL system. I was thinking about an 8XL or a 9XL running on a MM. Would this be a good setup? Initially I would run 14 nimh cells but am looking to run 4 lipo cells.
Would the MM handle that or should I go with something else?
Does anyone know what kind of speeds and run times I would get with either setup?
I'd like to be in the 40 to 45 mph range and at least 15 to 20 min run times.
Any input or experience would be much appreciated
Thanks