Need help on picking lipos?

[Brooks]

Hi there

I have just bought a Losi 8ight 2.0 E Buggy and i need some advice on lipos. I am reading Marvins Brushless setup guide and it has been very useful but am still unsure on what Voltage to run and capacity. I am going to be racing at Nene Valley which run Duration of the A final is 30 minutes, the B final 20 minutes and all others are 10 minutes and http://coventrymodelcarclub.club.officelive.com/default.aspx .I think i should make the B final or maybe A final so i am looking for a lipo to last around 30 mins. I have been looking at the new Ansmann Xirius Pro lipos:
http://www.ansmann.de/cms/racingroot/lipo-xirius-batteries/lipo-batterys-xirius-pro.html. Are they any good. :confused:
If you could offer any advise on which lipos to buy voltage, Capacity and C Rating. The Buggy is kit standard gearing 15 on a 45 Spur with a 2100KV Losi motor and speedo.

Thanks alot in advance
Chris B

[ek9russ]

I think the 30 min finals are for the large scale petrol cars, and 20 mins where for the 1/8th rallycross at the Nene. I think that was how they ran last year, though I could be wrong!

You could ask Ben aka unseenmagik on the Nene forum he was just about getting 20 min run times with his electric car… :)

[gnr racer]

If you have to run hardcase, you wont beat the Turnigy 4 cell 4500 from Hobbyking for value for money & they have just come back into stock.

[jasonwipf]

While most electric races are 10-15min I am used to those 20-30min mixed Elec/gas mains your speaking of. If you dont mind a battery change get those 4500mah hardcase that gnr mentioned.

A battery change can be done in under 30 seconds which will be about equal to all the gas pitting the nitros do in a 20-30minute main. So they shouldnt complain when you point that out.

The only reliable way to get 30min nonstop with hard racing throttle is probably 6cell 4500mah-5000mah which will be a huge heavy pack. I like 6cell cuz it runs cooler especially in the summer ( a 4cell 5000mah= 6cell 3200mah roughly for run time).

See http://www.oople.com/forums/showthread.php?t=37230 for more details on that.

[Brooks]

Thanks for the replys. Thats what i was thinking, The A B C finals at nene Valley must be mixed with Gas/Electric. I have read the other posts and have been some help. Is this true, a lower KV and a Bigger cell Battery (5/6 Cell), you get better duration and temps but this doesnt apply to higher KV motors :confused:. So in my Losi 8, its standard 2100KV motor, would be be better run with a 4 Cell lipo, true? The temps should not be as hot and the duration should last longer than using a 5 Cell with the above motor?

Also what do you guys think of the Ansmann lipos, 4 and 5 Cell at 5000mah 30C?
Sorry about all the question, still trying to get my head around it.

Thanks again
Chris B

[jasonwipf]

2100kv is 4cell. But no the higher the amount of cells the cooler things tend to be. I have no experience with the Ansmann.

[slipknot666]

turnigy or zippy flightmax 4s lipos are a good choice.

[dodgydiy]

my loong max tipple 5000 30c seem ok.

[richardmid1]

The cooler temps on higher voltage setups is not just because you use a lower kv motor, it is more about the lower gearing.

You can gear your car to last 30 mins easily.

Ide say you want your car to be at top speed/stopped accelerating 3/4 of the way down the main straight.

[Kamikaze_racer]

I took the LRP 5900mah with 50c they are great aswell. I think 5s aren't allowed?(In Germany not) Ok, maybe they are are very expensive but the Turningy 4500mah 30c are better than the LRP's but you can't drive as long as you can drive with LRP's

Kamikaze_racer

[jasonwipf]

wow if those things are 5s they are huge an heavy. Since the 30c does not blow its load as quickly as the 50c if you drove those 2 packs at the same tempo you'd be surprised how close they would be. In otherwords the 30c pack would get better mileage not only cuz it will run softer and cooler but the lighter weight would all work together to give better mileage.