If I lengthen a club by an inch, how much will it generally impact how far I hit it?
Generally a 1″ increase in club length will yield 1 mph of clubhead speed. 1 mph of clubhead speed increase = approximately 2.3 yards. Of course that assumes that you still hit the 1″ longer club in the center of the face.
I went to a 47 inch driver which I don’t hit farther than my former shorter driver. However, I hit it more consistently which makes my average driver distance farther since I now hit most drives well and in the fairway. The longer length makes me swing more smoothly. There is no way to know for sure without testing. By the way, a shaft will play a whole flex softer for a 2 inch increase in length.