Ok I have a question, I have explored running brushed on lipos, and I finally put question to practice. I hooked up my 3s zippy to my 13 turn and 10 turn speed controls and the brushed motors ran like brushless. The two speed controllers are rated at 150A, 5v bec's but have a max input voltage of 8.4V. They are Associated Auto and Auto Pro. Now if only they had LVC, I would have some real fun.
I think your exceeding the max input voltage with a 3s LiPo, at least if it is what you said it is. What do you mean that they ran like brushless? Yes they will be faster but thats because Lipos don't drop there voltage under load like NiMhs do. I have run my 1/18 late model on a 2s lipo with stock esc/motor, it's def a lot faster.
I only have two brushless motors, a Mamba 7700 and a Medusa 3100kv. It pushed my brushed motor like my brushless. Nowhere near as smooth thought but just as fast.
well power is amps x volts x efficiency. No reason why brushed motors can't pull amps and be efficient for a short while. How about seeing if it runs like a brushless motor 2 runs later, without changing the brushes and cleaning.
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Sub 7lb, lowest CG of any 1/8 buggy