Sonia - (my 2/100 euro's worth) looking at it practically: V1 is limited by Vr (ie. made equal to Vr) at the lighter weights (if theoretical V1 > Vr) because you can stop at Vr and after the rotation manoeuvre is started the performance calculation ensures that an engine failure can be safely carried through into the air. And since closing the good engine(s) and re-landing after Vr is not taken into account there is no point having V1 higher than Vr.
Let's say in your example of V1 being 160kts but the a/c weight and conditions on the day give Vr=130 (say). You might be able to stop from 160kts on the runway, but since 160kts > Vr you would be well established in the climb and you would probably not be able to re-land and then brake inside of the TORA (theoretical, of course, because such a manoeuvre would be, er, dramatic to say the leaast - but it demonstrates why V1 is limited by Vr?).
Of course if something more significant than a single engine failure occours after V1 or Vr then you need to think outside of the perf A box.....
Is this where you were coming from in your question??