anyone run 3S in a Truggy?
 

Just out of curiosity, is anyone running their truggy ( or tested their truggy ) on a single 3S Lipo?
What sort of speeds would be possible "theoretically" without puffing the pack?

People who are geared for 25mph might be...

Not sure what kind of info you are looking for, but higher voltage is always better. Lower voltage will demand the use of a very efficient motor, such as a neu, to perform and not kill batteries. You still need the same amount of power to get those truggy tires turning and move the weight of the vehicle, regardless of how much or little voltage you run.

So you will need the same physical weight battery, regardless or voltage to get the same runtime and power. So either a 3s 10000mah, or a 6s 5000mah, for example.

You will need to run the same size motor for any given voltage, for example you want motor rpm around 35k rpm, and want to move a 10lb truggy. A neu 1515 is a tried and tested motor that can get the job done. You would need a 1600kv motor for 6s, or a 3200kv motor for 3s. A 3200kv motor in a 10lb truggy geared for 40mph on 3s lipo will be pulling some amps, I bet 250 or more spikes, and well over 100 average. Stuff gets hot at that level, esc, motor, wires, plugs, etc. Plus you need a good battery to handle the load.

Higher voltage is just better all ways round. Now that we have the MMM, an inexpensive esc capable of 6s, there is no reason to not run 5-6s in the heavier vehicle. It just makes more sense. Going even higher in voltage would be better, I would prefer to run 8s, 10s or 12s. My varied experiments with 8s and higher have been very positive, especially on heavier vehicles and higher gearing.

Not a good idea really... 35mph tops is about what you should expect using a pack with something around 6000mah cap... the currents will be too high for comfort using such a low voltage.

You would need a very good pack to do this, at least a 30C and 6000mah or more of capacity.

Why would you want to run such a low voltage pack? You really don't want to go below 4s lipo, even then you need a good quality pack for a truggy. It's just asking for trouble, everywhere, pack, esc, motor.

I run 2s for training mode for my son - 4S gearing so get about 20mph...

thanks guys, I was just sitting at work wondering what sort of speeds would be possible (you know . . .wasting time at work bored), thanks for the answers.

Most everyone will advise against it, but most also have never tested it out and continue to advise against it via heard word. That's fine and if you want to stay cautious, that's good.
I'm one that has no problem running 3s on my truggy. No batteries, my truggy weighs about 7lbs. It's really not that heavy of a truck and I don't have any fancy CF parts either to lighten it up. I don't run a single 3s pack, but 2x3s packs in parallel. Each pack is rated for 90A, so total of 180A capable (supposedly). On 3s with my gearing, my truggy hits about 40mph. I've bashed and run at the track with zero problems on 2x3s packs. On an 80F day at the track, my ESC was 80-90F, my motor was 90-100F, and my batts were 100F.
I've tried running single 3s packs a few times to see what happens (and I really wanted to get some runtime in and was impatient) and 2 of the packs had 1 cell die (so 3s became 2s). No puffing. Just a dead cell. Need to open the packs up and either make another 3s out of them or make a 4s pack.

Is it the best scenario? No. It's true that it pulls more current. Less current is better.

Is it a setup that can run with no problems and everything stays cool? YES!!!

In case you're interested to know, my BL setup is an EZRun 150A ESC and 3674 motor. I also run on 4s. Not a super efficient, high dollar setup. Yet it still runs great and allows me to pass nitros at the track and out jump them on the jumps that don't have a lot of runway to pick up speed.

BS

I run 6s, Neu 1512 3D(1700kv), when geared for 35mph I get ~130F for motor, and up to 100F for my highly modified Quark, that's on a 80F day at a race... the temps are more like 150+F when bashing.

Sure you could get those temps, if you were crawling around going 10mph. lol

Call it what you like. Those are the temps I get. I'm not full throttle at the track except on the straights, which aren't that long and run for about 15 minutes at a time, so my temps aren't that high. Even when bashing, my temps have never exceeded 140F on an 80+F day. I've yet to run it when it gets really hot here (90-105F), but so far so good for me. Believe what you like, but since you've never tried this setup, been at my local track, etc. then it's only your opinion based on your experience with your particular setup. My statements are facts from my runs and experience with my setup.

i think ur facts are wrong as well, i also call BS if it was that simple every one would run that setup

BS as well, I run 4s1p 25c 5000mAh packs with CC Mamba Monster 2200kv 48t/15t gearing in my 8ight-t i see 125-135f temps on motor 125ish+ on ESC and 100f on batteries on a 90f day. Temps on a 3s are going to be more then that. Retemp or quit reading your gun in Celsius mode.

they way you write it, I would believe your figures. It's easier for people to say "noo, that doesn't work"... still, it's hard to believe.

the negative of high voltage is the extra weight. 4000mah 4s is lighter then 6s 4000mah. every gram of mass extra, you have to accelerate and stop. this causes stress on the components. your cars isn't heavy, so it's not that hard work for a 74mm motor.

I have once read, that in 1:1 car racing every extra kg requires xx horsepower to be the same fast. that's why I don't like today's cars with all that electric extra stuf nobody needs. that's why I like my vintage benz...

I call BS too. I raced quite a bit with a 3s setup in a buggy with a 1512 1.5d (3300kv) motor. It worked pretty well, but the battery temps were pushing 140+ degrees. I eventually puffed a 3s 6000 25c PQ pack and used a 3s 8000 Maxamps pack. There is no way a 3s setup geared to run with nitros on a medium to large track is going to run efficient.

On smaller tracks, 3s is more than adequate though.

I wouldn't say that the motors and esc run dramatically cooler, but the batteries definitely aren't nearly as strained. The batteries on my 5s setup rarely break 100 degrees on a 80 degree day as long as I don't run them down to the LVC. As batteries improve, it may be possible to run lower voltages without much risk though.

The difference is in the efficiency/run time. I can get the same run time out of a 5s 3300 that most guys are getting out of 4s 5000/5500 packs. I know people racing with 6s 2600 packs. I have RACED a full 24 minutes straight during an A Main to LVC on a 5s 5000 pack on a big ass track. There is no way a 3s or 4s setup will ever get that kind of run time.

Your statement may be true that addl weight causes addl stress, but that is not a negative of higher voltage setups. If you run a 4000mah 4s pack and go to 6s, you reduce the mah to get the same runtime. The weight of a battery per watt is pretty much fixed. So if you want X mins of runtime at X speed you will end up with the same weight battery regardless of voltage.

Basically a 4s 4000 packs will equal an 8s 2000 pack. Keep in mind you will run a motor with half the kv for the 8s setup compared to the 4s. Plus amp draw will be less on the 8s setup (half or more) and that will provide better efficiency due to the lesser voltage drop on the 8s setup.

There is no negative aspects to a HV setup. Currently not alot of choice in escs for cars over 6s, and finding a good charger can get expensive. Also, 6s seems to work well for 1/8 scale, so no real need to go up to HV unless you are going for higher than normal speeds, or have a very heavy vehicle.

And guys, don't jump on jsr so hard about his results. He has not listed his gearing, so we have no idea what speeds he is getting to, and we have not seen the track either.

Given the fact he is only running 15min I think this is why his temps are so good. I set all of my vehicles up to provide 25min min of runtime. The first 10 mins barely gets anything warm. Plus his esc has a fan and his motor may well have a fan on it too, as it is the HW system. Plus if he uses decent batteries that will keep system temps down as well.

His recomendation is based on his usage, which is the only thing I can fault him on. If you want a truggy capable of 40mph+ and 20+ min runtimes, 3s lipo will not be the way to do it. Not easily. 4s is marginal, 5s is much better.

I was thinking of using a a 3s 8000mah 20C TrueRC pack in a 3.3 Revo conversion running a HV 6.5 Pro on my small LHS track. Sounds like this might be Ill-advised even considering the Revo conversion is pretty light weight ? The track is almost always dry and dusty so I was thinking 3s will not be over powering and provide adiquet power with the tracks surface, Now I'm Confused ??