Help me understand.

[_paralyzed_]

it depends on the batteries and speed control you plan on using, in general a slower kv motor with more volts is better

[notnodak]

I'll be using a MM esc w/ UBEC and either 12 or 14 cells.

My unbderstanding is that the 2600 in a E-Savage witha 18t ponion on 14 cells will go about 40 and not get to warm but I also thought that a lower kv withould handle more gear better also. I'm not sure if I have the setting on the speed calculater in correct could some one try these motors on it so I'll have a better idea. Actually if I just knew the size and balloning factor to fill in for Stock Revo wheel/tires I could probibly do it myself.

Thanks for the help.

[_paralyzed_]

since you are running the mm i'd go with the 2600kv. you are limited to 4s or 12 cells with the mm, (some have run 14 cells or 5s, be careful!) so the motor is closer to the sweet spot (35,000rpm) with the 2600kv, an overall matched system where you would be under volted with the 1800kv. on the speed calculator balooning doesn't really matter and 6 is a good number for a revo diameter

[lincpimp]

Keep in mind that both of those motors have 5mm shafts, so you will have to buy a 5mm bore 32p pinion. I would suggest the 2600 on 12 cells, the MM can definately run that.

Check this out, I figured a 18t pinion would be your best bet, as it would keep the system cool and give decent speed.

Differential Ratio: 2.8461538461538462
Transmission Ratio: 1.7222222222222223 Emaxx 2nd gear
Spur Tooth Count: 66
Pinion Tooth Count: 18
Total Voltage: 14.4
Motor KV: 2600
Tire Diameter (inches): 5.75
Tire Ballooning (inches): .1
Spur/Pinion Ratio: 3.67 : 1
Total Ratio: 17.97293 : 1
Tire Circumference (inches): 18.69 inches (474.79mm)
Total Motor Speed: 37440 RPM
Vehicle Speed: 36.87 MPH (59.23km/h)
Effective Speed Rate: 2.56mph/V (4.11kmh/V)
Effective KV Value: 2600