The top weight just allows the ball to be close to balance after drilling the holes. If after drilling you have too much top or bottom weight I would think the ball would lope down the lane or possibly hop if it was extreme.
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16-17 mph,350 rpm,PAP 5 1/2 x 3/8up, HighGame 300 x 3, High Series 782
Book Average 215 / 205,PBA Xperience ave180