I understand how any connector will cause/create resistance which we all know the list of effects it will have. I run two five minute heats and one main - and the wires are warm but not to hot to touch. I also check the motor temps after each time out. I have been averaging 135 to 140 temps. If you keep the wires short, that will help a little too.
I am running 72% throttle, Gens 5000 - 7.4, 40c, Pro4 4600, MMP, 62 spur with a 13 or 14 pinion.
I am going to the track tomorrow with my son to test out some changes. I will check the temp of the wires.