The big runtime question?

VillageIdiot · #1 08-01-2012

Im struggling to figure out how long I will get on each run on the lipos.

I have tekin t8 rx8 combo with a 2050kv motor, 16pinion, 46 spur gear and 90c 6500mah lipos x2 to run 14.8v

now all the figures are out I cant find anywhere to calculate an rough/close figure of what runtime it will get before a battery change is required.

basically id light to know what runtimes id be getting and average mah usage per minute.

all the guides ive been finding give me stupid calculations like a 15mph top speed and 7 minute runs

D20MCK · #2 08-01-2012

Can you not just set a reasonably safe li-po cut off voltage on your speedo and run the car till it stops?

badger5 · #3 08-01-2012

Why don't you try the 'selecting the right kV motor for your 1/8th buggy' thread in the 1/8th electric section, http://www.oople.com/forums/showthread.php?t=88179

You might want to go down to a 15t pinion with that motor as well, this will also increase run time.
With the mAh/minute estimate from that thread of 320 you will just about manage 20 minute on your 6500mAh Orions without any spare. But that is assuming that you can get all of the 6500mAh out of the cells. To tell this run the car until the cells dump and see how much they take on the the recharge.

VillageIdiot · #4 08-01-2012

how long are 8th finals, or 8th EP finals?

tempted to get some intellect 6800mah lipos

badger5 · #5 08-01-2012

In the US they are normally 10 minutes, still to be decided in the UK though but I think normally 20 minutes, will depend on the club etc.
Demon Power Products have some 70C 7000mAh for sale at £70 each, not sure how good they are though. Where can you get the 6800mAh Intellects from though?

VillageIdiot · #6 08-01-2012

from the US you will find them through fleebay

VillageIdiot · #7 08-01-2012

Im not convinced with those, wouldnt part money with them.

I will hold on to the orions and see whats decided for EP. 5mins qualifying and 15mins final should be decided really, eliminate the need for pitting.

Ross · #8 08-01-2012

Quote:

Originally Posted by LIP

how long are 8th finals, or 8th EP finals?

tempted to get some intellect 6800mah lipos

The 1/8 RX ep nationals will be running 15 min finals this year if that helps.

My Mate was getting 18 mins from a 5800 Zippy pack today at Coventry, he runs a tekin with a 1700 motor in a Mugen 5R buggy. Having said that, he got 20 mins from a thunder power 5200.

davidmog99 · #9 09-01-2012

I know its not really the same, but i have an ansmann vapour rtr electric 1/8, bought while bored on holiday for bashing.
Im running a single cheapo 3s 3800, and get 12 mins.
Thats with a 3050kv motor. Your 4s setup should be much more efficient, and your battery capacity far higher, i would expect you will easily get twenty minutes.
I raced at my first 1/8 meeting at crewe and when my nitro broke, i raced it and it looked fast. (i crashed every corner with both, im a shit driver and am just getting back into it). In fact, after i got lapped (which was a lot) i was trying to keep up with the nitros on the straight and soon noticed my electric was definitely faster on acceleration and top speed.
If you are racing against the nitros, you will have to pit anyway. If i were you i would pretend i were lewis hamilton coming in for a drive through penalty. "is it cos i is electric?"

VillageIdiot · #10 09-01-2012

so long as the finals are 15 - 18mins then ill stick with the orions and get some more for qualifying.

I really feel the EP 8th class should be together seperate from nitro and exclude any pitstops. far smoother to race.