Krio

iTrader: (159)

If all you want is runtime, 10th scale is the way to go. Grab a solid truck and throw in an 8000mah 2s lipo and let the good times roll.

nichocgn

iTrader: (2)

In general 10th scale can run 30 mins with hard driving on a 8000 mah battery. If you want long run times and low cost on the power system 10th scale is the ticket. A slash or some other "basher" worthy truck that is tuff as nails can hold up pretty well.

In general 8th scale takes twice the battery in weight and cost as 10th scale. No it is not an exact cost\weight but a good ballpark guide.

I would not run 8th scale on less then 4s in my opinion. And if you want to race you might want to settle on 4s if you are running roar events.

You can either buy a 4s pack or run 2 - 2s packs to get to the 14.8 volt.

I would also look at 20C 5000 mah as the min raiting for the batteries for 1/8th. For most people that seems to get from 13-18 mins depending on driving and setups.

Some of the conversion threads have great info that you might want to research if you are doing 1/8th scale. It is failry new and prone to more headaches for some people.

R40Victim

iTrader: (1)

Well, a single, 4S battery, that has more than 5000 or 6000 mah, will be HUGE and very HEAVY. You need to think about it in those terms. It might make run time, but it'll end up so heavy you can hardly drive it.

Also, you need to decide which battery, and which car, as well as which conversion. Some conversions are designed with two 1/10th(2S) batteries in mind. Other conversions, use a single 4S battery.

What car are you planning to use? Have you picked a conversion, or are you still hunting?

RaV3N

The batteries Im using are 6500mah 30c 2S. I want to do a saddle configuration with two of them. Whats my best bet

R40Victim

iTrader: (1)

Well, there are several cars that can run that configuration. The Caster Fusion is a purpose built brushless 8th scale buggy. Novak makes conversions for several buggies, all using two packs. But I really don't like the Novak stuff. The Novak HV systems have proven unreliable at my track. I've seen about 10 of those fry, and they weren't mistreated. Also, many 2S packs can be run stacked side by side in a single battery tray, which would open nearly all the other cars up to you.

If I were you, I'd get either the Caster or the Losi 8ight. The caster should work with nearly any 2S packs, there's no conversion, you just pick a brushless system and go with it. The losi will fit two 2S packs on their side, and since the 8ight's center diff is to one side, it accommodates the single battery tray very well.

Do you have a brand preference at all? Is there an 8th scale buggy or truggy you like the looks of, or have seen turn fast laps at your local track?

ta_man

iTrader: (168)

A caster buggy (designed for two 2S pack) and a 2000KV motor like a Neu 1512 2.5D. Jason Maxamps runs that setup. Unlikely that you will get 30 minutes runtime out if it.

R40Victim

iTrader: (1)

His track could be smaller, and his driving style "adjusted for efficiency" However, I agree, he's unlikely to make a full 30 minutes.

RaV3N

Well in order to estimate my runtime put it this way, With a Novak GTB / velociti 6.5R brushless and that battery I get a 35minute runtime in a rustler xvl 18/83, and Im only on my 4th cycle of the battery. So what do you think is the best configuration to stay within 30min range?

R40Victim

iTrader: (1)

Well, the 8th scale systems have a much higher amp draw, because the vehicles weigh more than double what the 10th scale stuff weighs. You will NOT likely be able to run for a solid half hour, without building a car that weighs too much to handle well at all. You can't make 30 minutes in an 8th scale with those batteries, it's too heavy.

WRPracing

iTrader: (3)

I ran a pair of SMC CMAXX 5200's (4S total) on a medusa 2000kv mugen/caster conversion using an 80amp Hobbywing esc and got 25min of runtime. I TQ'd and took 2nd, so I wasn't slow on a 200x100 track.

I feel confident I could make 20min main with this setup. (I wanted to gear up one tooth)

To go 30mins you would need at least 50% more battery, so 5200 + 50%= 7800mah.

Therefore an 8000mah 4S pack would do with a small margin of error.

SMC is coming out with a 8600 or 9000 4S pack soon. That will be the ticket.

R40Victim

iTrader: (1)

How much will that battery weigh? My 4S 4900 weighs a little under 500 grams. My 4S 5000 Losi hard cased pack, weighs 630 grams. Something to think about. You might make run time, but if you're too slow to win the race...what's the point?

WRPracing

iTrader: (3)

From Maxamps site:

Lipo 8000HV 4S2P 14.8V Battery Pack


More Information
# 8000mah Capacity
# 14.8 Volts
# 44mm X 137mm X 50mm
# 20C Constant(160 amps)
# 30C Sustained(240 amps)
# 50C Burst(400 amps)
# 725 grams


One LB is 454 grams...... It's 1/8th scale... If you want to go hang for 30 mins with the nitro's, you have to carry around an extra 1/3LB or so... It's not like dragging a lead acid car battery around.

R40Victim

iTrader: (1)

One way to find out! Plus they'll likely make you pit at least 4-5 times to make it fair. In that time, you could do one battery swap, and save all of that weight.

Also, I tried to vist the site in your sig, and this is what I got:

"Forbidden

You don't have permission to access /cgi-bin/ on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
WebServerX Server at www.teamwrp.com Port 80"

Is the site down?

WRPracing

iTrader: (3)

Yeah, our site is down... The member hosting our site moved to another province and the site was lost. I'm currently rebuilding it... sorry.

A battery swap is what I would do personally, but it is possible to run the whole 30 with batteries that are out there now.

R40Victim

iTrader: (1)

What will the car weigh with that much capacity on board? Could a car that heavy still handle ok? My car is over 8lbs with a 4S 5000. I'm pretty sure you'd be close to, if not over 9lbs to get that much battery on it...