Does anyone know the max cable lengths for the 5v run from the pi to the relay, the gpio runs from the pi to the relay, and from the relay to the motherboard reset pins?

I have my rigs in 3 separate racks and would like to utilize 1 pi in total and 1 relay per rack (3 relays total). The cable lengths from the pi to the racks would be 18 ft, 14 ft, & 16 ft respectively and the cable lengths from the 5v relays to the motherboards would be 3 ft, 4 ft, 5 ft, 6 ft & 7 ft respectively. I'm not too concerned about the runs from the relays to the boards but I'm worried that 14-18 runs from the pi to the relay are too long. Can anyone weigh in?