Have a 29 inch hobby boat that I put two 550 , 17 turn, 4100 kv motors brushed motors in. Has 35 mm props. Looking all around the net and forums for formulas, etc, to figure out what amp size brushed esc I should be getting. Anybody have some info or formulas for calculating max amps? Thanks

(no comments please on going brushless - brushed motors ar in to stay until they burn out)

Oops forgot - running 8.4 volt NIMH 3000 battery.<br type="_moz" />

Anybody? Not looking for exact answer. Restated: about how many amps(50 - 100- 150-?) will a couple of 550 size (4100 kv/8.4 vNIMH) in light plastic boat pull at steady run full throttle. Thanks in advance.

ha, just read this over on offshore. Check your answer over there. I believe they are saying a 90 amp speedo would be good. If you expect to pull 50 amps i wouldn't get a 60 amp speedo for a boat. Since you will likely be using full throttle a lot, 10 amp head room isn't much.

Can i ask why brushed? Is this stuff you already had? The worst brushless motor would probably be better then the best brushed motor in my opinion.

Already have the motors and mounted. Its a 42 dollar boat that I don't want to put much money in. Popped the esc that came with it on initial run and therefore the search. Going to purchase stuff that I can use later on when I deep six this one. Thanks for the reply.

Be mindful that if you buy a brushed esc it will not work with brushless motors when you come to update.

Go to Offshore and buy the 700 and be done with it and use a 60 amp esc and get a couple of 3.5 lipos in parallel and a 440 prop and have something.