What runtimes are you all getting then...?
 

Just wondered what runtimes everyone is getting, if anyone could let me know, along with what motor/cells your using?

about 20minutes on some ftx 5000mah 7.4V 20C packs in a Losi 8B with mamba monster esc, medusa motor and rc monster motor mount.

i have some zippy-R 14.8v 4500mah 21/35C's on the way and would imagine they would give a similar run time...

I'm getting about 12 minutes driving hard. This is with Flightpower 4S 4350mAh Lipos in a Hyper 9E. Motor: Medusa Research 2000kV motor with a Castle Creations Monster Mamba.

Soon I'm looking at getting some 5S ~4500mAh Lipos to get that run time to about 15 - 16 minutes.

Managed a 15 minute nitro final using a FlightPower 4S 4500mAh 30C and a Neu 1512 2600kV motor.

Where from?

hi, i got them off the french ebay site. they are a bit long for my battery trays (about 3cm too long) so i may sell them as i have to strap them to the top which is neither safe or good for low COG.
if you are interested PM me an offer (i have 2 4s packs)

EDIT: i forgot to say these zippy-r lipos are far better than the other zippy lipos and are reported to be made of enerland cells in korea...

i had a simlar prob with the 14 volt trackpower lipos at neo but found that i could turn the cels on there side and run them diagonal across the tray. this ment they still ran on the chassis line although i did have to cable tie them in lol. now got to try and find some 10k mha lipos so i can do a 30 min final :P as want to kick some nitro ass :thumbsup::woot:

I did a 15 min final at a border counties league last week and pulled in for a lipo change at 10 mins just in case (was grass track so didnt want to risk it). Pit team did a great job of swapping it in 23 seconds lol !!! and still managed to win by a lap :p

What are the exact dimensions?

Haha yeah that pitstop rocked!!

what mah and kv were you running by the way? Had chance to see what was left in that first lipo by the way?

I was running a Tekin 2650kv motor and they were 3700mah packs in the final. havent discharged them yet so not sure. If i was more prepared i would of ran the 5000's ;) But hey ho :)

Any tips on where to get batteries? Hoping to race in may but only have one pack!

Not really, i picked up a couple of 3700's from the airplane section on ebay, apart from that there are some good value packs from hong kong at about £40, they may be only 20C rated but the 3700's that i run are 20/22C and the car wasnt slow :)

I would look at Flightpower packs (either eBay or almost all model shops that sell Heli's/Planes) as they are fantastic quality and you can get them in practically any Voltage, Capacity or Size. Otherwise 2 Trakpowers in series or any of the car race packs really (Orion, LRP/Nosram, Core RC etc).

The Overlander Tornado packs are also worth a look; good quality cells, reliably rated and in various sizes. They tend to be slightly cheaper than Flightpowers though, but are still very popular in Helis, so many places sell these too.

Were you running 4S 3700 ?

Are thunderpower any good?

Yes, Thunderpower are also good. They are made from very similar cells (from the same manufacturer) as the Flightpowers. PolyQuests are also worth a look.

Yes were all 4s packs, Maxamps, thunderpower and flightpower

20.6cm long, 4.7cm wide, 2.8cm tall

Arse. It won't fit in my car either.:(

So, I'm not sure how comparable different makes are, but running losi electrics with the 2100kv motor, if I go for 4200 4S cells they should definitely go for longer than 10 minutes yeah?

I'm hopoing to enter a few meetings where finals are 22 mins, I have one 5000mah 4s pack (the losi one which by all accounts is a bit s**t), would that and a 4200 4s see me through 22 mins easily enough?

what is the C rating of the 4200?
my 5000's that have about 4550 left in them can easily do 15 minutes flat out but it depends on gearing e.t.c

As electric says, it depends on the gearing and stuff, but, geared to the same speed as the nitros I get about 12 minutes with 4350mAh 4S so 10 minutes with 4200 should be easily acheivable. Also, as you are already an electric driver, you should be a bit smoother anyway, so you should be able to get more run time than me
(faithful nitro driver originally; throttle on "waaah - waaah - waaah" through the corners:lol: - not good for battery life)

It'd be 40C, the 5000 is 15c I think. Not an ideal balance having 2 such different cells, but on a 2100kv geared sensibly (to nitro pace) should they do 22 mins between them? And should the 4200mah ones manage a 10 min heat?

The capacities should both easily make 10 minutes each (probably about 11-12 minutes).
15C is unlikely to be powerful enough. (5*15 = 75A). Most people reckon that you need about 100A continuous. Also it does depend on the Burst current available. With my Flightpowers I have 50C burst (4.35*50 = 217.5A)

you will probably be better off running 20C's.
burst is only for a few seconds though and for most of the run you won't use very many amps at all. take a 5000mah pack for example if you get 10 minutes runtime out of it (quite short i know but if you really are tearing it around a track possible) you are only using 30A average over the run ;)

However, it's the bursts that kill the lower C packs off. My set-up has bursts of about 150A, which a 15C pack (which is probably only capable of 25-30C burst), even of high capacity, is unlikely to be able to provide, and so will probably puff.

It's ok, I put the wrong figure, it's 25c in reality!

Think for my first meeting I'll just not run the final, tbh I want to be able to make 25 mins on 2 packs of 4s, one of which is 5000mah, and not sure 4200mah in the other pack will give me enough will it? May need to get another 5000, will that give it enough?

I say give the final a shot, you don't know what sort of run time you are going to get until you've tried.

I would have thought that you could get 25 minutes between the two packs, I use 4S 4350 and get 11-12 minutes on a rough track, so probably more like 13-14 on a smooth one. 5000 is 115% of 4350, so you should (hopefully) expect 115% of the run time (12 * 1.15 = 13 minutes 48 seconds - perhaps a bit exact...) but 12 + 13 and a half is 25.5 so should be enough. Just don't do the warm up bit at the start, turn the car on and stick it on the line with 15 seconds to go.

Yeah actually from that they should last (especially considering time lost in pitstop too), what I mean't was I haven't actually bought the 4200 yet! I'm only planning one meeting before mid July, so might just do the first (in May) with just the one 5000 battery then not finish the final, and wait to see what comes available over the next mth or so battery wise, rather than getting a second one right now! Might leave me better set for the meetings I'm doing later in the summer!

Dave

Oh, I see. That's a pretty good idea to be honest. As for the 2nd battery, I would still go with non-hardcased 14.8V as the quality of the packs are generally better than the hardcased 4S packs.

I can get around 30 minutes or more from an 8000mah 3S battery, running a MMM 2200Kv combo on my Xray 808.

Iv got a Castle MMM/2650kv set up, and iv ordered some 22c 5000mah packs, but i really want to try it out! Iv got some newish trakpower 20c 3200mah packs from my b4. I know the C rating is a bit low but do u guys think they will be ok for a few short runs? Anyone had any experience of running them in 1/8th? Im dying to drive it but not at the expensive of puffing lipos :(

cheers,
Ben

I have 25C flight power cells and Max amps cells, 22C Tornado packs and a Flightpower 20C, and to be honest i cant notice the difference so i think you will be fine, especially over short runs, i managed to get 21 mins out of the Flightpower 5000mah on a loose dirt track, obviously if you are on something like grass or astro where you have the grip your run time will reduce a bit.

The Castle Creations Monster Mamba Max states in the instruction manual not to use anything less than 5000mah for a reason! I would not try it with your 3200mah packs as they will have too much current drained from them and are likely to puff up and become useless.

I've got to agreewith AmiSMB with this, 3.2A * 20C is only 64A continuous, which is not going to be enough. Running packs under 5000mAh is fine, but the C rating must make up for it, so you would need 30C packs at least for 3200mAh to be fine. Even then they will be quite pushed 3.2 * 30 = 96A which is about right but they will get quite warm and won't last as long (i.e. as many cycles) as a larger capacity pack that isn't as stretched.

Guys, if running 2x2s will 4mm connectors handle the load ok?

yea that should be fine :thumbsup:

also you should only use a pair of lipos if they have the same amount of use otheriwse you will puff one as i found out the hard way with some 2s lipos :thumbdown:

I've been trtng to ask about this in another thread, is it safe to charge the 2 batteries separately or do you need to try and do them as one?