performance potential w/ 6s lipo?

Hey guys just wondering which feigao motor would do well with a 6s lipo.
Im currently thinking about 8000mah but it costs an arm and a leg. What kinda run times would I expect out of a 8000mah over a 5000mah? Would I be able to gear higher with 8000mah batteries? Would the whole system stay cooler with 8000mah batteries? Thanks for your help

[BrianG]

When you go with higher voltage, you can choose a motor with a lower kv/higher wind count, which will help runtime. Also, less current is used to get X amount of power so any current losses are less as well.

You generally shoot for 35k rpm as the max motor rpm. To pick a suitable motor, just take 35000 and divide by the voltage. That will give you the motor kv to get. Then, just find a motor with a kv in that range.

Runtime increases by going to 8Ah from 5Ah depends on what you are getting now. Assuming you are using the same motor and gearing and voltage: If you get say, 30 minutes on the 5Ah, 8Ah will give you 48 minutes theoretically.

thanks for the speedy reply.

So getting a higher mah battery will only increase runtime? No other advantages?

I was thinking about a 7XL feigao since a lot of people use that and seem to be happy.

[BrianG]

Another benefit with going with higher capacity cells is that the voltage will most likely drop less under load. If both the 5Ah and the 8Ah cell are rated for 20C, the 8Ah cell will be able to deliver more current. If both are pulling 100A, the 5Ah cell voltage will dip more because you are running at its max rating.

If you are running 6s lipo, I would go with a 10XL. The 7XL will be MUCH too fast and hot and you will probably end up burning it up. A higher wind motor can go just as fast, but you might have to gear up to get the speed you want.

I was hoping for a top speed of 60mph. Is that expecting too much from a BL savage?

[BrianG]

Well, it's possible with the right motor, battery, and gearing. For that kind of speed, you'll probably want a cooler running motor like a Neu or an LMT along with 6s or more lipo, and pretty tall gearing.

Well Im waiting for castle to come out with their mamba monster max. If I can't wait any longer I'll just go out and buy a feigao 10xl and a esc. I can't afford a neu. I rather spend more on a batteries than the motor. Will I atleast get 50mph on the 10xl geared up?