I just coverted my engine from a 22t down to a 17t orion sv2 method, great little engine btw. now the question is; how do i know what mah batt to get to keep up with the demands of the new engine. the batt i'm using is a nosram 7.2v nimh 4600mah.
any thoughts[8D]

It won't be too particular, anything 3300 and over will do the job. The bigger ones will simply run longer.

That battery is fine. I use IB cell 7.2v 4200mah batts with my 17T motors. By the way, technically, electrics run on motors and nitro uses engines. Not a big deal at all, but switching the terms can confuse people in certain situations. If you want more speed you can always still upgrade to an 7cell 8.4v battery!

will upgrading to a 7cell 8.4v battery fry anything??

As long as the gearing and/or load isn't too high a 17 turn motor is fine on 7 cells. 8 cells would be about the max that I'd recommend.

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