Hi Mehmet,  You can expect to see an increase in distance by switching from a 909D3 to a 913 D3.  Based on our testing, you shoud see increased ball speed as well as lower spin and both will contribute to more distance. On a robot using stiff flex speed assumptions, the gain is 8 yards.

Another benefit of switching is that the 913 has our industry leading Surefit adapter, which will allow you to obtain a more precise fit through customizing your loft and lie to your specific needs.  This customization will provide an even greater potential for increased distance. 

The difference in miniscule. I would venture, that you would not yourself get the 8 yards  as indicated by the robot test, but perhaps 4 yards in carry in generel. Knowing that both drivers have a max smash factor at 1.48 the ball speed should be the same. Spinn might be different, and yes that could increase or decrease the distance.

Have you tested one to see for yourself?  The new 915 might be worth looking into which should be out in about sixty days or so.