darcness

iTrader: (3)

I'm looking to buy so new batteries that are a bit higher quality than my current ones. I'm really looking at the Turnigy Nano-Tech's in the hobbyking's USA warehouse. I'm having trouble deciding how much capacity I actually need to run my mains. Here's what I have for reference...

8th scale - AE RC8.2E:
Motor - Castle 2200kv
ESC - Mamba Monster
Main Times - 7min or 10min (mostly 7min)

10th scale - Kyosho RB5 SP2:
Motor - Turnigy 3900kv (3650 - 380 can)
ESC - Turnigy 35 Car
Main Times - 7min

I'm just looking for a "safe" capacity to run. I'm thinking that I need at least 2650mah for the 10th scale and at least 3300mah for the 8th scale. Those are probably what I would actually run during the main, so obviously I would go a bit higher just to be safe.

Thoughts, suggestions?

crusey_aus

iTrader: (3)

Impossible to guess runtimes without some idea on your average amp draw

What speed are the cars geared for and what size is the track ?

Do you have existing packs you can throw in the car and get a baseline ?


Cheers

GLwagon

iTrader: (22)

There are a few other factors to take into account for battery choice...

-weight, smaller packs are lighter.
-voltage roll off, the smaller packs will start showing a little less voltage sooner.
-overall amperage capacity, 5000mAh 30c = 150amp, 3000mAh 30c = 90amp, 3000mAh 40c = 120amp.
-do not exceed 80% capacity is a general rule (3000mAh = 2400 usable)

I personally run a Turnigy 6000mAh in most of my 1/10th scale cars, the most I've ever taken out in 6min was around 1800mAh.

My 1/8th scale currently is a 1400kv on a 5s, the motor draws almost nothing & is plenty fast. I have some 3600mAh 30c & they will last 7-8min.
for the Mains I need 4400+.
I push the batteries a little bit in my 1/8th.
The hotter the motor the better the batteries you should get.
2200kv is a monster, & I'd start at a 150amp pack or better...
4000mAh 40c = 160amp

darcness

iTrader: (3)

Thanks for the feedback guys, I ended up going with a 65c Turnigy Nano-Tech 5000mah for my 8th scale and a Zippy 5700mah 50c for the 10th scale. Should be good enough for me.