ok. i want some SERIOUS advice

[Finnster]

I too have the TrueRC 4K cells, but in an 8K pack. I think 4K is too small. I think the motor you are looking at is a bit small too. A 1940 at a min. A 1940/7 on 4S would be great. The MM may or may not like 5S, I wouldn't bank the setup on it.

You should be getting ~120A peaks, which is alot for a 40A continuous cell. Driving is very peaky, and I think you will overdraw and heat up the cells. If you really want low weight you got to pony up a bit. I'd at least get the 5K cells if you are determined to stay cheap and 1P