Battery questions for summit

[jwalker497]

I have a Stock summit vxl running it with 1 stock battery. Its great but id like to go a little faster SAFELY without having to modify anything else so i have 3 questions

1) can i run 2 nimh batteries safely and will this increase speed?

2) if i run 1 lipo will this increase speed

3) can i run 2 lipos safely keeping the truck stock?

[jwalker497]

3 can i run 2 lipos without keeping the truck stock?

[dcfox]

1 Lipo increases the speed dramatically.
You can run 2 lipos parallel to increase run time...but don't series them. the motor/ESC can't handle the voltage.
I'd recommend running a single Lipo instead of two.
The extended run time running two will heat the motor up pretty good.
After running mine with a Venom 1300 20c 11.1v lipo...I don't think I'd want it any faster. It flat out hauls.

[jwalker497]

So what traxxas lipo battery should i get for the vxl?

[dcfox]

PM coming your way.

[jwalker497]

How about this one?

Check this out on AMZN: 25C 11.1V 3S 3-Cell 1400mAh Lipo Batty:TRA 1... http://amzn.com/B005FUKPLO

[dcfox]

That appears to be the one that Traxxas recommends.

[robl45]

you don't need 3s, you are going to break things on 3s with this truck. I run 2S and its plenty fast for my son and for me when I'm playing with it. 3S would be like my big truck where its really not fun anymore IMHO.

[dcfox]

I agree to a point.
You definitely need serious throttle control when running 3s.
I've already broken parts.(both center shafts and an axle shaft.)

I put the Traxxas wheelie bar on mine...and with a Lipo...it's useless from a dead stop.
it will still do a standing backflip(I think it's even easier with the wheelie bar,lol)
It does help tremendously when grabbing the throttle while you are already moving.

[pavmentsurfer]

The worst traxxas 1/16 vehicle to run on 3S is the summit. The larger tire size and more extreme angle of the drive shafts due to the longer travel rockers and arms will result in overheating issues and broken driveshafts if your not very careful. You CAN do it... but the amount of self control you have to use while your driving almost makes it less fun. Get a couple good 2S packs and you can hold the truck full throttle and not have to concentrate so hard on throttle control. Plus, you wont have to worry AS MUCH about heat. Itll still get hot. They all do. But not nearly as fast as with a 3S

[jwalker497]

So which battery should i get, preferably traxxas?

[robl45]

You CAN do it... but the amount of self control you have to use while your driving almost makes it less fun.

exactly, my lst2 brushless truck is rediculously fast and doesn't break from the power like these would but its so fast that its not even fun to drive.

[jwalker497]

So far these are the most powerful traxxas lipos i can find traxxad 2820

http://traxxas.com/products/models/electric/72074summit116vxl-batteries

Right now i plan on using just 1 lipo - is it an improvement in speed and runtime over the stock nimh?

if i run 2 at a time - will that break stuff on the car? I dont want to have to change gearing etc. Also what part do i need to run 2 lipos at the same time?

What part do i need to run 2 nimh at the same time?

Traxxas website says speed will be increased just by running a second battery is this true?

[westoakmech]

If you run 2 2s lipos you want to parrallel them. That will not break any more than 1 2s lipo, it will just give longer run times. Just 1 lipo will give you little difference in run time. The difference in top speed from a nihm to 2s lipo is not alot. But the power, and time to get to top speed is way more. You will need a tra3064 to run 2 2s lipo's

[jwalker497]

Thanks west!

If i wanted to run 2 stock nimh would i newd a diff paralell connector?

[robl45]

Thanks west!

If i wanted to run 2 stock nimh would i newd a diff paralell connector?

connector would likely be the same, depends on the connectors the battery has.

I wouldn't run two at a time unless its really cold where you live. The small stock nimh maybe, but the lipos will are larger capacity and likely will cause overheating problems if you run 2 at a time.

[dcfox]

Right...most 2s Lipos I've seen max out at 8.4v.
In series that gives you 16.8v...which is more than the max rating of the motor/esc 14.4v.

From what I've found...top speed with a single 3s Lipo is just about the same as you would get with 2 nimh packs run in series.
A single 2s lipo should be slightly slower.

[dcfox]

The series connector and parallel connector are the same price...and your LHS will probably have both in stock.

FYI... be sure to change the settings on your ESC when switching from nimh to lipo and back.

[pavmentsurfer]

You run 2 or 3s lipos in parallel only. But you can run the stock nimh packs in parallel Or series. Parallel for more run time or series for more speed. In series you'll get a lot of heat. You'll get a lot of heat with 3s as well. If you want to run it all the time you need to gear down for sure. But with a 2s you should be safe to just run it with no changes.

[dcfox]

Ok..I'll ask a couple questions...

Does anyone have data about top speed differences between two nimh in series,one 2s Lipo and one 3s lipo?
I'm pretty sure that the top speed will be about the same for the 3s lipo and the pair of nimh in series.
What I'm curious about is how much slower would it be with a 2s Lipo.

[westoakmech]

If you are getting heat issues with 2 2s lipos in parallel, then you probablly need to gear down. 16 tooth pinion is stock, I run an 18 with 2 2s, and have no heat issues, unless I am running in heavy grass.
The adapter will be the same with nihm or llipo. 2 nihm's in series is pretty fast. Two nihms in series would be about the same speed if not a little faster than a 3s. That is of course where the heat issues arise though.
One 2s or 2 2s will be the same speed, just more run time. With 2 2s 1300 mah in parallel, I get around 40 minutes plus depending on the type of running I am doing. IMHO 3s, or 2 nihm series, is just to fast and out of control, I enjoy the running, compared to the repairing. It also hard on bodies, because you spend alot of time upside down, LOL

[dcfox]

It also hard on bodies, because you spend alot of time upside down, LOL

That ain't no joke!!!
LOL...agree 100%

I might go pick up a few good 2s lipos and put these 3s away until I get my KB Fiesta.

[yellowufo]

Ok..I'll ask a couple questions...

Does anyone have data about top speed differences between two nimh in series,one 2s Lipo and one 3s lipo?
I'm pretty sure that the top speed will be about the same for the 3s lipo and the pair of nimh in series.
What I'm curious about is how much slower would it be with a 2s Lipo.

Are you using stock esc??????

[dcfox]

Yes...the Velineon VxL3m.

[pavmentsurfer]

In a brushless vehicle speed is all about voltage. I cant give you exact numbers but as a very VERY inaccurate generalization, a 3S will be ABOUT (again, very loose generalization) %50 faster than 2S. 2X nimh packs will be every so slightly faster than a single 3S for the first few minutes of the run, then they will equal out (once the voltage in the NIMH batteries begins to drop).

A single 2S lipo charges to 8.4volts, a single 3S lipo charges to 12.6 volts. A single 6cell NIMH pack charges to about 8.2 volts so 2 of them would charge to around 16.4 volts. BUT, the little 1/16 NIMH packs deliver very low amps... so the pack is constantly being stressed. This causes the voltage to drop MUCH faster than a decent lipo. So while the difference in 2X NIMH packs is more than 4 volts higher than the 3S lipo, the lipo will maintain its voltage LONG after the NIMH packs have dropped their voltage to well below the voltage of the 3S lipo. Put simply, at first the 2X Nimh packs will be faster, but only for a very short time. The 3S lipo will be faster for nearly the whole run.

The 2S lipos run in parallel will give you LONG run times... thats the way to go for sure.

[robl45]

i'm in south florida, after a run with a 2s 2200mah lipo, the motor and esc are hot. running two of those parallel would be a bad idea.

If you are getting heat issues with 2 2s lipos in parallel, then you probablly need to gear down. 16 tooth pinion is stock, I run an 18 with 2 2s, and have no heat issues, unless I am running in heavy grass.
The adapter will be the same with nihm or llipo. 2 nihm's in series is pretty fast. Two nihms in series would be about the same speed if not a little faster than a 3s. That is of course where the heat issues arise though.
One 2s or 2 2s will be the same speed, just more run time. With 2 2s 1300 mah in parallel, I get around 40 minutes plus depending on the type of running I am doing. IMHO 3s, or 2 nihm series, is just to fast and out of control, I enjoy the running, compared to the repairing. It also hard on bodies, because you spend alot of time upside down, LOL

[dcfox]

I agree robl45...I'd rather run a single lipo...and let it cool down for a few minutes between runs.

[jwalker497]

Ok while appreciate the info - i think i'm more confused! Let me see if i understand. Again i want to aboid breaking stuff or changing gearing etc.

1) So running 2 nimh is parallel safe, in that i wont break anything. this will give me more runtime but no more speed!

2) 2 lipos in parell is also safe

3) 2 nimh in series is too much and will risk breaking stuff.

4) 2 lipos in series is way too much

5) 3s lipo is too much as well and may break stuff

6) to run lipos or nimh in paralell, i need traxxas part TRA3064

7) to run lipos or nimh, i need traxxas part 3063

[yellowufo]

Ok while appreciate the info - i think i'm more confused!

So running 2 nimh is parallel safe, in that i wont break anything. this will give me more runtime but no more speed

2 lipos and 2 nimh in series is too much and will risk breaking stuff.



1 3s lipo is too much as well and may break stuff

I run 2 nimh in parallel the trucks balance is much better with 2 packs.
for me i wont go over 7.2 volts seen to many problems with the esc and drive train issues, never broke a hing cept a knuckle and that was my fault. Im geared 18 50

[jwalker497]

I run 2 nimh in parallel the trucks balance is much better with 2 packs.
for me i wont go over 7.2 volts seen to many problems with the esc and drive train issues, never broke a hing cept a knuckle and that was my fault. Im geared 18 50

To run parallel i need traxxas part TRA3064, correct?

[yellowufo]

[QUOTE=jwalker497;5394696]To run parallel i need traxxas part TRA3064, correct?[/QUOTE

Dont have my manuels close but look at the site it is there]

[dcfox]

Ok while appreciate the info - i think i'm more confused! Let me see if i understand. Again i want to aboid breaking stuff or changing gearing etc.

1) So running 2 nimh is parallel safe, in that i wont break anything. this will give me more runtime but no more speed!

correct.

2) 2 lipos in parell is also safe

also correct

3) 2 nimh in series is too much and will risk breaking stuff.

voltage will be at max 14.4v... will break things if not careful.

4) 2 lipos in series is way too much

too much voltage...will overheat motor/esc or both.

5) 3s lipo is too much as well and may break stuff

throttle control will be very important to keep from breaking stuff.

6) to run lipos or nimh in paralell, i need traxxas part TRA3064

correct.

7) to run lipos or nimh, i need traxxas part 3063

That part # is for running two nimh in series (lipos in series would be too much voltage for the motor/esc).

[robl45]

I run 2 nimh in parallel the trucks balance is much better with 2 packs.
for me i wont go over 7.2 volts seen to many problems with the esc and drive train issues, never broke a hing cept a knuckle and that was my fault. Im geared 18 50

Balance better, but will be slower than Lipo. plus you adding more weight.

I don't see the fascination people have with running this thing on 3S. I've raced and run RC cars for 25 years and 2S is more than fast enough on this little truck.

[dcfox]

I bought 3s not j.owing any better being new to the hobby. I bought what my LHS suggested.
Knowimg what I know now... I would have bought 2s packs.
Not going to waste these...so I'll just have to be careful.

[jwalker497]

So if I run 2 NIMH in Paralelle WHich traxxas or venom battery is a good choice and will fit the Summit VXL?

[dcfox]

2 of the same Traxxas nimh that came with the Summit would be perfect.
Does Venom even sell nimh battery packs?

[yellowufo]

So if I run 2 NIMH in Paralelle WHich traxxas or venom battery is a good choice and will fit the Summit VXL?

i run 2 1600 mah nimh iv not seen any higher
Mah

[yellowufo]

Balance better, but will be slower than Lipo. plus you adding more weight.

I don't see the fascination people have with running this thing on 3S. I've raced and run RC cars for 25 years and 2S is more than fast enough on this little truck.

Never said it was faster then lipo.. slower with 2 packs yup but u cant tell thats why i went 18p.

[robl45]

Never said it was faster then lipo.. slower with 2 packs yup but u cant tell thats why i went 18p.

inefficient compared to lipos but whatever floats your boat.

[dcfox]

I agree with robl45.
From what I've noticed...the NIMH starts out fast...and gets slower as the battery pack drains.
The Lipo seems to have full speed until drained...and then just stops completely .