Amp draw/efficiency question

[nitrostarter]

Ok guys. A friend and I are in the process of setting up Ofna Hyper SC10's. We both have Neu 1509/1Y 3600kv motors that we run and they do a pretty good job.

My question is being that we are limited to 2s lipos, would I experience more efficiency and less amp draw by running a 1509/1.5D 4500kv?

Of course I know that efficiency increases as the Kv drops and the voltage rises. However we are limited to 2s voltage. So that leads me to my next understanding of Neu motors being most efficient under 30-35k rpms. So the 4500kv motor would but it right at 33,300rpms and at a higher rpm throughout the throttle range.

Both motors are plenty strong enough for these trucks on my track. We are trying to reduce amp draw to extend run time. I would love to step up to 3s on the 1Y but can't.

Help is appreciated.