Do the shafts from the 909 drivers fit the new 910 drivers. I have a shaft from the older model fitting cart and would like to try it in my new 910 are the interchangable? If not does Titleist offer a way to make them interchangable?

As a rule of thumb, for every 1/4" over length you add 1 swing weight.  I would bet your clubs are in and around the D6 mark.  Different shafts will obviously affect swing weight as well.  KBS is a good example.  The balance point is higher and results…