Let's face it the writers original 'Startrek' series pretty much ignored Newtonian physics so we will do the same. Ships have mass and you clearly need more power to move a bigger ship. So :-
'Sub warp' travel is powered by 'impulse*' engines. These give a ship velocity (not acceleration) as follow :-
Velocity = Impulse Power / Ship mass
*Nothing to do with the use of the word 'impulse' in classical physics.
For a ship to get into 'warp space', 'hyperspace' or whatever it needs 'warp engines'. Doubling the number of warp engines does seem to half the time it takes to get anywhere but it does not double the 'wrap factor'. Most ships can make warp 5 but very few can make warp 8. From this we get:-
Warp Velocity = Warp Power / Ship mass
but
Warp Factor = Fudge Factor X log( Warp Velocity )
Jartrek universe (or will be) a multi dimensional space. Locations in this space are uniquely identified in a coordinate system.
T = Time, in ticks, since creation of current universe.
U = Universe number. The laws of physics are consistent within any universe. (effectively game number)
W = Warp number. A ship using warp drive has an equivalent location in x,y space but cannot interact with it.
X = x pos in universe (units currently undetermined)
Y = y pos in universe (units currently undetermined)