brushless motor rpm's

[daniellewis]

just a quick one
if any one can help us out
if running a 4s lipo is there a limit of rpm/volt in which u should run
or does it depend on the prop and the amps which it will draw

the boat in which it is going into
is a df vortex i think it 21 inches long
etti 150a esc
x637 prop
4s 5000mah batt
any info on what motor should i purchase
as i an only new at electrics and have no idea as yet slowly learning

[Rumdog]

I used to have that exact same boat and setup. On 4s you'll want around 2200 kv. A feigao 540L is a great size motor for this setup. A ul-1 motor would also be a good choice as well as the AMMO 2300.

[daniellewis]

is there any difference running an xl motor at 2200rpm/volt
running the same prop
will it lower the amp draw ?
or do u need to run a bigger prop to keep the rpm's in check
as the motor will be able to spin the prop easier

there is the feiago 540l professional motor which i think has an rpm of 2150/v is this suitable
any info