All a longer or shorter rod does is lengthen or shorten the overall length of the cylinder. A long rod just means a tall cylinder. The piston still moves the same distance up and down and still has the same stroke. That's why the old Holland Hornet 049 was short compared to the TD 049. They had the same stroke but the Hornet's rod was a bit shorter. Problem is that a short rod puts higher side loads on the piston and cylinder