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Slaphead View Drop Down
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    Posted: 17 February 2013 at 7:34pm
Hi Guys and Gurls,
 
Im looking to get back into RC Cars along with my eldest son.
 
When i last powered up my car it was brushed and had 1700scrc's so al this lipo and brushless stuff is a mistery to me.
 
I've been looking around and narrowed it down to a choice of two speedo's but cant make up my mind so any feedback on these would be much appreciated.
the first is a hobbywing extreme stock the other is a reventon pro both along with the pro setup boxes an 13.5 motors.
 
The other question is about lipo's. What sort of ampage would you need for a five min race 4000, 5000, 6000. and what is the "c" rating.
 
Thanks in advance,
Sam.
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paul_A View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote paul_A Quote  Post ReplyReply Direct Link To This Post Posted: 19 February 2013 at 7:16pm
there seem to be not so much difference between Hobbywing and Speed Passion when using a 13.5T …
… and have a look at the Reventon R Combo which should be a good compromise in price without a noticeable difference in performance to the Pro (if you stay away from low winds)

from my experience with a Mi4CP powered by a 13.5T: I am using about 2000 mAh in our 8 minute races (indoor carpet or outdoor tarmac) > I admit that I am not in the winning circle but I am not the slowest – it is just my lack of practice LOL

C–rating is a (theoretical) measure for the maximum current output related to the capacity (C = capacity in Amps) > example: a LiPo rated at 5000 mAh/30 C should be able to deliver a maximum of 150 A(!) for a very short period of time

p.s.: hope my English is clear enough …
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Slaphead Quote  Post ReplyReply Direct Link To This Post Posted: 19 February 2013 at 10:35pm
Hi Paul_A
 
Thanks for the reply, btw your english is fine.
 
I've been looking at the reventon pro souly because i've been reading so many bad posts on forums about the "Reventon R". So i was wondering what the Pro was like as i cant find many posts about them, apart from the price of them keeps droping, which is always a worrying sign. the extreme stock has realy good reports.
 On paper specs the Reventon Pro is by far the better ESC, but i wanted some feedback realy from people that have used or got experience of them.
 Same with lipo's realy having never had exepience of them i didnt want to spend silly money buying the most powerfull lipo's i could find to be somewhere in the field without having to compromise on power/ gearing just to finish a 5min race. So the ratings of capacity and punch were a bit lost on me realy as there is alot of differance capacity wise between 1700 and 6800mah.
 
Thanks again fella, and if anybody else wants to jump in with more info or help then it would be much appreciated.
 
Cheers,
Sam.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote paul_A Quote  Post ReplyReply Direct Link To This Post Posted: 19 February 2013 at 11:45pm
hi Sam,

if you are thinking of 13.5T brushless or so than a LiPo with 4000 to 5000 mAh and 35+C should be really sufficient – at least for hobby use/just4fun

most important for using LiPos is a suitable charger (LiPo programme!), a balancer (nowadays often integrated in the charger – to keep the cells on equal level) and a safety bag (just to be on the safe side) > and never charge batteries without having an eye on it

gearing is still important > electric motors don't like it to get hot (loosing magnetic field when getting over 100° Celsius or so)

and in the days of 1700 mAh batteries I was quite happy to make 5 minutes with a 17t brushed geared correctly …
… now it is no real problem in making 5 minutes with a motor having more power (and much better efficiency) without the need for expensive top grade batteries
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Slaphead Quote  Post ReplyReply Direct Link To This Post Posted: 21 February 2013 at 5:30pm
Originally posted by paul_A paul_A wrote:



if you are thinking of 13.5T brushless or so than a LiPo with 4000 to 5000 mAh and 35+C should be really sufficient – at least for hobby use/just4fun
I wanted to take my eldest son racing at our local club, mainly fun for me with my old authritic thumbs but im hoping my boy will do a bit better with his young playstation / texting thumbs......Wink
 

Originally posted by paul_A paul_A wrote:

most important for using LiPos is a suitable charger (LiPo programme!), a balancer (nowadays often integrated in the charger – to keep the cells on equal level) and a safety bag (just to be on the safe side) > and never charge batteries without having an eye on it
 
I've bought a relitivle new orion iq605 charger so should be ok there, been reading about charging and that seems quite idiot proof charging at 1c as for the sack was gonna get one as its better to be safe than sorry.....Wink
One thing i will ask about lipo's that i hope you can answer if you can the rating i.e. 2C/1P - 2C/2P. I understand the first part denoting how many cells are in the pack and that denotes the voltage of the pack, but what does the "P" stand for?

Originally posted by paul_A paul_A wrote:

and in the days of 1700 mAh batteries I was quite happy to make 5 minutes with a 17t brushed geared correctly …
And so can i.......i was running a pro-cat at the time with a 17double, just upgraded my old 1400scr's to 1700scrc's thought i had loads of power but you still stood there waiting for the cell dump hoping and preying to make the 5mins......LOL, that takes me back.
Cheers,
Sam.


Edited by Slaphead - 21 February 2013 at 5:32pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote paul_A Quote  Post ReplyReply Direct Link To This Post Posted: 22 February 2013 at 12:48pm
2C/2P and 2C/1P denotes the internals of a LiPo pack
> 2C stands for the number of cells connected in series = giving the nominal voltage of a pack
> 2P stands for the nummer of cells connected in parallel
so in a 2C/2P are actually 4 single cells

for hobby use there schouldn't be much difference between 1P and 2P packs …
… and for competition use please ask some pros (maybe to get different answers) > I am too old for that   ;)
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Slaphead Quote  Post ReplyReply Direct Link To This Post Posted: 22 February 2013 at 11:31pm
Hi Paul,
 
No cheers for all your help it is much appreciated, cos all this modern tech is like wading throuh treacle to a simpleton like me.
Plus i dont see many pro's steeping up to help? As all the guy wants is a little help to get back into the sport.
 
thanks again,
Sam.


Edited by Slaphead - 22 February 2013 at 11:34pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote mutley001 Quote  Post ReplyReply Direct Link To This Post Posted: 23 February 2013 at 8:19am
Hi Sam
I race competitively using 5000 lipos rated at 35c and these are more than sufficient for a 5 min run in a touring car running 13.5 and 10.5 motors only taking out 2000 mah from the pack per run. The configuration of the packs is less important and really doesn't mean a great deal in performance in my opinion so it comes down to cost and personal preference.
The 2 speedos you have suggested are both good esc's. The hobbywing is a little dated now but still fast enough to keep up with all but the top class racers, the speed passion one should be good enough to see you run all sorts of classes and motors right up to the very highest level, but is obviously more expensive. It's down to your preference at the end of the day and how much you want to spend.
What ever you choose to run, take care you get the gearing right for the track and motor you use and you should get plenty of life out of your equipment.
All the best with getting back into the sport/hobby

Paul
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Slaphead Quote  Post ReplyReply Direct Link To This Post Posted: 23 February 2013 at 9:49pm
Hi Paul ,
 
Thanks for your reply. It's interesting to know about the lipo's as i said above they are a dark art to me along with modern electric.
 
If the truth be known over the last few days i've ordered both esc's as apart from Paul_A there has been no help or advice coming forward so i got both and thought i would do my own comparison. Not the cheapest way to start but it means both me and my son have got modern esc's to go on with.
 
Cheers,
Sam.
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