I'm looking to remove 15' of wall between my living room and kitchen. It's the center bearing wall of a two story colonial. On the second floor are bedrooms. The existing floor joists are 2x8's 16" on center. Normal snow load, gable roof bearing on outside walls. Basically I'm supporting the floor and ceiling of the second floor. If possible I would prefer it flush, but if it can't be that's fine.

How does this play out from the beam in the basement. That can also be an issue here shifting the load.

Since the joist are only 8 inches I would use a mirco lamb for the new beam This can be added to its sides to 'fit" the profile of the wall. Also they company has the engineering specs you are looking for.