opinions wanted! will 5000 15c 6s zippy packs power a xt8

[tc3_racer_001]

as the title explains. ive got some zippy 6s 15c 5000's for another project here and am curious as to what people think will happen in a xt8 with 1512 finned 3d 1700kv neu motor, MMM and geared for 30ish mph.

the idea was that my old buggy 18mths ago was stupidly powerful but ran a little too hot for our summers (australia, think 45 degrees C in the shade!) so i sold it and now am building up a truggy :)

now i dont want as much power as last time becuase im aiming to race this beast haha. will the 15c packs cut the mustard or do you guys think they will drop their voltage and possibly swell. i KNOW there are better packs for sure but for $40 it was worth a shot working on the idea i can get the same amount of power on 6s (say 500W) at 22A than at 4s at 33A... keeping in mind the low gearing is it possible? i will surely get another pack 30C either 5 or 6s depending on how fast it turns out to be. my other thought was having 2 packs in parallel but its already pretty heavy (700g of battery is enough!) may end up getting a 3600 or similar 6s pack to lose some weight but keep the amps up. (same amt of watt hrs as a 5000 4s pack...)

anyway let the arguments BEGIN. please keep in mind my requirements/setup... :)
EDIT: i might add these packs boast a 5c charge rating (not that ive tried) so they should be somewhat decent cells? either that or the manufacturers are promoting central heating in the form of lipo fires!
Ryan

[jhautz]

Originally Posted by tc3_racer_001

as the title explains. ive got some zippy 6s 15c 5000's for another project here and am curious as to what people think will happen in a xt8 with 1512 finned 3d 1700kv neu motor, MMM and geared for 30ish mph.

the idea was that my old buggy 18mths ago was stupidly powerful but ran a little too hot for our summers (australia, think 45 degrees C in the shade!) so i sold it and now am building up a truggy :)

now i dont want as much power as last time becuase im aiming to race this beast haha. will the 15c packs cut the mustard or do you guys think they will drop their voltage and possibly swell. i KNOW there are better packs for sure but for $40 it was worth a shot working on the idea i can get the same amount of power on 6s (say 500W) at 22A than at 4s at 33A... keeping in mind the low gearing is it possible? i will surely get another pack 30C either 5 or 6s depending on how fast it turns out to be. my other thought was having 2 packs in parallel but its already pretty heavy (700g of battery is enough!) may end up getting a 3600 or similar 6s pack to lose some weight but keep the amps up. (same amt of watt hrs as a 5000 4s pack...)

anyway let the arguments BEGIN. please keep in mind my requirements/setup... :)
EDIT: i might add these packs boast a 5c charge rating (not that ive tried) so they should be somewhat decent cells? either that or the manufacturers are promoting central heating in the form of lipo fires!
Ryan

It'll work fine if you keep the gearing low like you said. I would also set the LVC on the esc a little higher than normal. Say 3.4v/cell. The Zippys in my experience dont like to be run down to far or they tend to go badly out of balance and sometimes loose a cell. Buy setting the LVC higher I have gotten much better life from the cheap battery packs.

[tc3_racer_001]

yeah ive always opted for 3.45 for the cutoff regardless of the packs.

[tc3_racer_001]

well it works... well! still pulls some wheelies but have settings turned down. pack survived first run no worries. warm but not hot thats for sure! very happy. now have a 30-40C setup i can compare stats with. im also thinking the motor will stay cooler with the 15C packs do to restricted current flowing... not that i can call it restricted. i can tell the batteries are working hard though because after 2 or 3 takeoffs from a standing start they are alot less powerful. i will be nice to these packs now i think - either that or just see how long they last! will attach wattmeter to it tomorrow.

[tc3_racer_001]

quick update... FAR OUT is all i can say! chucked in 2 4000mah 30-40C 2s zippy lipos (may be turnigy - cant see through the fibreglass tape i useD to hold them together!)

i swear its just as fast, with more oomph than the 6s... so im rather baffled now. the 6s performed well but these are amazing, cant wait for the soldering iron to heat up to change the plugs on my watts up meter! sede which setup makes more peak power.... i think the 6s will but only just. now looking for another 2s pack to make a 6s combo :D

the weight is alot less and balance would be getting close to right with the 2 smaller packs. runtime, dunno it lasted 15 mins bashing around and everything was strangely cool! i love 12*c nights!

[kalbien]

What gearing you ended up with in the end?

I guess 6s will be fine, but when you really hammer it down and lots of current will be needed, batteries just won't deliver it. Also 6s 5000c is probably about half a ton heavy, that will make a huge difference as well...

[tc3_racer_001]

yeah the weight difference is quite large! 11/48 (stock xt8 spur) on both voltages. will try my 13 and 16t on 4s. plenty fast enough on 6s for my purposes! looking for another lipo but they are out of stock and dont really want to pair them with a 40-50C lipo...