2s in 1/8 buggy

[steveo]

has anybody tried 2s in a buggy, i see that neu has a 1415 1d at 4100 rpm could this work i am sure a high c rating battery would be needed would the MMM hold up to this

[BrianG]

It depends on gearing. Either way, current draw will be high to get the typical ~300w average/~1000w bursts that buggies tend to pull when geared for ~35mph. Not to mention greater losses (heat) from the increased current. Personally, 3s would be the absolute minimum, 4s typical, 5s-6s for "hv" setups.

If you have 2s packs, I would just use two in series with a ~2000kv motor.

[steveo]

i run 4s with a medusa 3680, just curios if that is possible would be nice to have a lighter buggy

[BrianG]

Well, I would start by determining your current power requirements using your current battery capacity and runtime. Once you know that, you can estimate the amperage at any voltage, and then see if your batteries are up to it. This page may help with this: http://scriptasylum.com/rc_speed/power.html

But a quick example; If you are getting 20 minutes of runtime on a 4s 5000mAh battery, and you want the same runtime and speed, you will need a 2s 10,000mAh battery on the appropriate motor.

[Semi Pro]

2s does work in a buggy but its not worth the trouble, i ran mine sub 6lb carbon 8ight with a 1409 1Y geared for 33mph on 2cell last year trying to drop the weight even further but it ran hotter than i would have liked plus the lack of torque really kills your acceleration.

my run time on 4200mah hyperions was sub 9min and the packs were over 120 comeing off, so i gave up.

in the end i went back to my 2600mah 6cell 1400kn setup

[lincpimp]

If all other factors are identical, you will need the same total wattage to run regardless of the battery voltage. Getting there will require virtually the same weight battery, so no beifit is found dropping voltage. Plus lower voltage eual higher amp draw for the same output, so you have to run larger gauge wiring, etc. HV is the way to go.

[outlaw]

During the time i builded my SC10 4x4 RC8 based
i tested 2S in that car and i was quit impressed how good it worked

I had a Tenshock 2220/7 4300KV laying around

Same gearing as for 2200KV on 4S 16/46

Just drove done the road, but wasn't slow at all and had enough punch
Was smooth driving

I bet, the CC 1410 from the SCT Kit would do a good Job here as well

Setup
Tenshock 2220/7 4300KV
2S 6500mAh 60C
CC MMP
Gearing 46/16 AE RC8 ex Nitro

[simplechamp]

I can understand running 3S in a buggy if you are going for an ultra-lightweight setup, but I think 2S is too low. Next thing you know people are going to be trying 1S 1/8 buggies, I'd love to see how that works out!

[E-Revonut]

I think that if you where geared for no more than 25MPH you could pull off 2s with a good battery but I wouldn't try for any more speed than that. It could be a decent setup for a smaller indoor track or a small backyard track. I would think that if you where geared near 40 on 4s and just dropped down to 2s with the same gearing you would be fine.

[outlaw]

I have my RC8 setup for 3S and it is mot any slower than 4S
I have drivetimes around 20-25min with 6000mAh
And my RC8 does weight 3,7kg

No reason for me, to go to 4S
There is enough power in the house

[outlaw]

Some Datalogs

TS 2220/7 4300KV on 2S in my RC8

Gearing 44/16

almost 180 A and close to 1200 Watt ...

[snellemin]

I ran even less voltage in my GTP before and got about 30mph with 2s2p A123.

[BrianG]

Assuming that 180A spike happened at the same time as the 1200w spike, that means the voltage was at 3.33v/cell on a 2s pack. Not too bad if that voltage is at the end of the run, but if anywhere else on the graph, that tells me the current is too high for the pack and would benefit from using 3s and more moderate gearing.

High currents are hard on everything, and is less efficient (heat losses).

Just my $0.02.

[snellemin]

Yea, my setup was running hot for sure. But it was doable.

[outlaw]

Jep the voltage dropped to 3,3 V
Was just a test for that little 40mm Motor....
3S would be not a bad idea...

On 3S the Motor will do about 45K
So 50/12 gearing should give me about the same speed as me 2240/5 Setup on 44/14
I will try that on friday

Guess 1200 Watt should be enough for that car...