Temperature is HUGE! I have found that out the hard way in testing some big inrunners of late. It really doesn't matter what the watts and amps are what matters is what is the motor temp, ESC temp and battery temps are with a given setup. What I am saying by that is: If you can keep the temperature of the motor below its rated maximum you can keep pushing it. This temp will depend alot on the cooling air that is able to get INTO and OUT OF the airframe.
Don't go by what the printed specs are on the motor either...for instance specs that say a motor can take a certain number of amps and watts with a certain battery because I have found that those numbers are false and misleading. If the motor is cheap and has a high resistance it won't take much...trust me! If it is sold as an EDF motor it probably needs to be in a 200+ mph tunnel of air to take the numbers that are given for it or it will burn in another airframe other than an EDF...don't ask me how I know!
During your motor tests start paying more attention to temps of the different components and do not exceed them or something will burn. Do not run your BEC or receiver off of the flight pack if you are going to be pushing the limits of systems...don't ask me how I know! You mentioned 5S and the red flags just popped up. 5S Turnigy packs have a board with a Z of solder that will de-solder at 250amps... how do I know...I did it and lost a plane!
There is very little PROP info on those ARC motors so I for one and others will be interested in how far it will go. If you do some prop tests please add it to the info on the Fast Planes...Big Inrunners thread.
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