Freewing Old Crow Engine Upgrade

[Jet Fixer]

Wanting to upgrade my Old Crow engine to try and get some more performance from the four blade prop. Stock configuration is a 4258-580kv motor and 14x8 four blade prop using an 80 amp ESC. Can I put a 4258-650kv motor in without changing anything else? I'm concerned that the extra speed of the motor might pull excess current and damage the ESC. Also, can a 4S, 4000mAh, 40C battery handle the bigger motor?

Any advice is appreciated.

[OV10]

Hello Jet Fixer
Don't know what extent of experience you've had/done with power mods to ePower warbirds regarding power factor knowledge or associated support equipment.
First let me say that anyone delving into altering motors from stock should at least have a Power Meter as part of the tool box for safer operations.
One of the most common, affordable and reliable on the market. https://www.motionrc.com/collections...yzer-gtp180awm
Having done many of FMS and Freewing/FlightLine motor changes over the years, the 650kV motor you are referring to is the FMS 1400 P-40B motor originally and is now also used on the FMS 1400 T-28.
That motor trying to twist up an additional blade is going to push to the max or exceed the motors amp rating of 60A. Power factors are not linear, they are exponential and every one of the parts of
motor kV&voltage in conjunction with prop diameter&blade count are acting upon each other considerably.
To turn that 14 inch 4 blade you would be a lot better off going with a 6S motor like the FMS 4258-kV460 which original came about with the release of the FMS 1500 P-47 which turns a 14 inch 4 blade.
FMS then later upgraded 1700 FMS F7F Tigercat to these motors which put more oomph in it's locomotion.

Be it known that the FMS motor mounts do not have the same mount hole spacing as the Flight Line mount so a little mechanical engineering mod will be required to the firewall mounting arrangement on the Crow.
Regarding the battery question, I have yet to see where a 40C rated battery won't deliver upon the demands of any prop driven warbird I've flown and there isn't a one of the Flight Line nor FMS and others that I haven't flown.

The capacity (4000mAh) is all relevant to how long you would like/expect to have for flight time.

Get the power meter and happy power moding
Best regards,

[Jet Fixer]

Hello Jet Fixer
Don't know what extent of experience you've had/done with power mods to ePower warbirds regarding power factor knowledge or associated support equipment.
First let me say that anyone delving into altering motors from stock should at least have a Power Meter as part of the tool box for safer operations.
One of the most common, affordable and reliable on the market. https://www.motionrc.com/collections...yzer-gtp180awm
Having done many of FMS and Freewing/FlightLine motor changes over the years, the 650kV motor you are referring to is the FMS 1400 P-40B motor originally and is now also used on the FMS 1400 T-28.
That motor trying to twist up an additional blade is going to push to the max or exceed the motors amp rating of 60A. Power factors are not linear, they are exponential and every one of the parts of
motor kV&voltage in conjunction with prop diameter&blade count are acting upon each other considerably.
To turn that 14 inch 4 blade you would be a lot better off going with a 6S motor like the FMS 4258-kV460 which original came about with the release of the FMS 1500 P-47 which turns a 14 inch 4 blade.
FMS then later upgraded 1700 FMS F7F Tigercat to these motors which put more oomph in it's locomotion.

Be it known that the FMS motor mounts do not have the same mount hole spacing as the Flight Line mount so a little mechanical engineering mod will be required to the firewall mounting arrangement on the Crow.
Regarding the battery question, I have yet to see where a 40C rated battery won't deliver upon the demands of any prop driven warbird I've flown and there isn't a one of the Flight Line nor FMS and others that I haven't flown.

The capacity (4000mAh) is all relevant to how long you would like/expect to have for flight time.

Get the power meter and happy power moding
Best regards,

I have never upgraded the power in anything. Still fairly new to all of it. Don't think I can fit a 6S in the compartment. I have seen another person that says he flies all of his 1400mm warbirds , including Old Crow, with the 650kV motor and has no problems. Just upped the ESC to 85 amps. I know that turning the four blade prop takes more power, but I do not know what the stock motor pulls or what the 650kV will draw. Thanks for the info though. It gives me something to consider.