On my road bike I have 172.5mm crank and my saddle height is 810mm from the bottom bracket. On my track bike I have a crank arm 165mm. Do I need to change the saddle height on my track bike? Will it make any good difference on my pedalling efficiency?
Saddle height for new bike setup purposes should always be set relative to the pedal, not the BB center or any other reference point. So yes, crank length makes a difference.
Using the ground or BB center as a reference point is convenient for re-establishing a given height after the post has been moved, but not for setting up one bike to have the same leg extension as another.
According to the rule of thumb method of setting saddle height (knee slightly bent when pedal at the bottom of the stroke) the saddle should be set higher if the crank is shorter because the pedal is higher at the bottom of the stroke. Essentially, seat height is set relative to the lowest position of the pedal rather than relative to the bottom bracket.
However, I strongly suspect that there are better ways to set saddle height for maximum power output on a track bike with short cranks.