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Old 02-11-2009, 10:42 PM   #136
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I have a question... So i did the math and the max amps that my motor will use is 52.7 amps... so does the C even matter as long as the amp out put is over that? I have no idea if the C would add in more power, but im almost sure it wont. If anyone has any insight i appreciate it.
Thanks Curtis
Higher C rate packs will run better with lower turn motors as the IR is lower which will reduce voltage drop and the pack will recover better from the high amp loads.
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Old 02-11-2009, 10:47 PM   #137
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Higher C rate packs will run better with lower turn motors as the IR is lower which will reduce voltage drop and the pack will recover better from the high amp loads.
okay cool. thanks for the info.
and also from seeing you represent your company and be involved and communicating with the rc community i have decided that when i get my next pack it will be an SMC. Just all the info and specs you give out and your confidence in your cells i know that i will be getting the best possible product
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Old 02-11-2009, 11:18 PM   #138
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Can some one please explain to me when you would ever need 200 amps of continous discharge or 400 amp bursts in 1/10th scale off road?
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Old 02-12-2009, 04:49 AM   #139
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Can some one please explain to me when you would ever need 200 amps of continous discharge or 400 amp bursts in 1/10th scale off road?
Sure, anytime you are racing, especially spec/stock. The only way it can deliver these kinds of currents is to have very low internal resistance. This lower resistance results in higher voltage at lower loads as well. Thus ya go faster. Aren’t working the battery as hard, I suspect it will last longer too.

Or your average electric 1/8 scale, those beasts eat weak batteries.
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Old 02-12-2009, 04:51 AM   #140
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Higher C rate packs will run better with lower turn motors as the IR is lower which will reduce voltage drop and the pack will recover better from the high amp loads.
Danny, thanks for the great info. This has been an outstanding exchange of information. Bravo, bud!
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Old 02-12-2009, 07:50 AM   #141
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ok this zippy bashing is getting out of hand. first off i will say that smc most definitly puts out exactly what they say they do and i will not debate that fact. however the 4s zippy h blue 5000 and the other white pack they have been selling are easilly capable of handling the demands of what a 1/8 buggy can throw at it and do it for about 100.00 shipped to you.
will they end up meeting dannys test, i dont know. but can they handle the approx 15 to 25 AVERAGE amp draw of a 1/8 buggy and do it for a lot of cycles if not taken too far down YES.
danny if you want to do a real world bench test then take 5000 packs and hit them with about 25 a draw down to about 80% capacity. that is roughly the same as a 10 minute main with a hot motor setup. do this cycle for a while and see what packs end up like down the road.
even if my zippy lipo loses some punch and capacity quicker than a pack that costs twice as much it wont be missed since these buggys have so much rip in the first place. heck i know of many very skilled drivers that already lower their throttle endpoint just to make the car driveable.

note, danny plans on testing the new zippy blue flightmax pack and not the more common H pack that most here already have.
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Old 02-12-2009, 08:30 AM   #142
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All I can do is speak from experience testing on the track. I started using Orion 3200 20C about a year ago. I still use these packs for mod buggy racing. It's all you need for modified. I started racing SS 10.5 about 6 months ago. First I bought the Orion 3600 25C and it definitely had more punch than the 20c. Shortly after that, the 3800 30C came out. It had a little more punch than the 25C. I purchased the Reedy 35C 5000 and the Thunder Power 40C 5000 for my tracks biggest race or the year. The Thunder Power 40C is definitely the best. It seems to have a little more torque, and the ideal gear is 1 pinion higher. ROAR switched to 13.5, and I sold my 25C and 30C, so I can't compare everything together.

With the batteries I have tried, there seems to be more punch with the higher C ratings. I'll do more testing in the next few weeks.
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Old 02-12-2009, 09:46 AM   #143
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but can they handle the approx 15 to 25 AVERAGE amp draw of a 1/8 buggy and do it for a lot of cycles if not taken too far down YES.
I don't think average draw is a concern, rather peak draw. And then past that maintaining voltage for performance, especially for those who don't have unlimited power, like spec/stock classes.

Don't need/want it? No problem, I think all we are after is honest true ratings so we can each decide for ourselves what to buy.
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Old 02-12-2009, 10:31 AM   #144
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kvrc: The Zippy test is basically done to learn more about the different prices of packs and the cost per cycle. Were doing this on flight packs as we want to show this info to the flight guys. I don't think doing it on a different pack will make a difference as I would hope that Zippy uses the same manufacturer for all there cells as this is what we do.

We can do the test at a specific amp rate as we want to compare it to our packs cycle life. So we must pick a C rate and typical cycle life test are done at 50% of it's true C rate. If we do a fixed amp draw it will not be fair as our packs have higher C rate.

I have never said that Zippy packs don't work or will have bad cycle life. I paid to get 2 packs to come to my own conclusions and I will post the results when they are done.
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Old 02-12-2009, 10:32 AM   #145
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dave h ....i am speaking specificly about 1/8 buggys in my post, i guess i should have made that more clear. and in 1/8 buggys the zippy packs stay cool and that is a good indicator of wheather the pack is being pushed too hard.
i think what smc had done in the past with their 35a draw turbo 35 testing is a much better real world test rather than seeing if a 30c 5000 pack can handle constant 150 a draws to prove wheather the company is telling the truth.
yes it is important that companies be as truthful as possible but as far as i know nobody in the battery industry has pushed for a standardized method so all cells are tested the same way. because of that what smc already has done is better and easier for us to understand.
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Old 02-12-2009, 10:40 AM   #146
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GFX numbers will only show part of the packs peroformance as when I test various packs at 35 amps I see some with similar numbers and voltage curves and when I go to 70 amps the difference is gets bigger.

The ability of a cell/pack to recover from amp loads will also make a difference in performance. That is hard to test for and show which packs are better. This typically has to do with the way the cells were made and what materials were used.

Bottom line is every Lipo being sold will take a charge and can handle being discharged in an RC car. Since there is atleast 6 manufacturers making high C rate packs that can be used in RC there are differences between packs even if this is hard to test for. So some packs wil have better punch/power than others and some will have better cycle life. Not every company making Lipos make them the same way with the same materials.
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Old 02-12-2009, 10:41 AM   #147
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kvrc: The Zippy test is basically done to learn more about the different prices of packs and the cost per cycle. Were doing this on flight packs as we want to show this info to the flight guys. I don't think doing it on a different pack will make a difference as I would hope that Zippy uses the same manufacturer for all there cells as this is what we do.

We can do the test at a specific amp rate as we want to compare it to our packs cycle life. So we must pick a C rate and typical cycle life test are done at 50% of it's true C rate. If we do a fixed amp draw it will not be fair as our packs have higher C rate.

I have never said that Zippy packs don't work or will have bad cycle life. I paid to get 2 packs to come to my own conclusions and I will post the results when they are done.
danny.... you are not who i was accusing of bashing zippy. the new flightmax 5000 packs they have are smaller and lighter than the zippy h blue and white r packs most of us already run. i dont know how they did it and i am a little suspisous about them. i cant comment on wheather those packs will be as good as the h and r packs that i have seen work great for many guys. the biggest problem with the zippy packs from what i hear is they dont hold up as well if drained really close to full discharge. the good news is in 1/8 buggy a 4s 5000 pack will do 10 min mains without really getting drained too far.
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Old 02-12-2009, 12:16 PM   #148
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2 different camps here. 1/8 scale where good enough is perhaps good enough for most, and spec racing where there is a best because tenths matter. Value is another discussion that may be more opinion since it means different things to different people. This thread is about false performance claims and that effects value, confidence and trust. Some companies have been flat out caught lieing about discharge rates. That should not earn your respect at any price.

I do have concerns that effect Tekin more directly in 1/8 scale. Poor quality batteries do cause problems with speed controllers and reliability. Especially 5S and 6S where the voltage is already pretty high and the additional voltage bounce poor batteries cause can exceed the limits of the components. It is like running the speedo without any caps on the battery line. Even a bunch of good caps cannot control it completely and the caps are prone to failure….. Causing speedo failure.

Last edited by Tekin Prez; 02-12-2009 at 05:14 PM.
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Old 02-12-2009, 12:21 PM   #149
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UN T1-T8 testing will be mandatory as of October 1st 2009 and it will not be self certification it will have to be from an official UN recognised lab. Up until that date I guess there is really no way to enforce it.

The ROAR saftey tests are good and this is why tracks should enforce ROAR Lipo rules.
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Old 02-12-2009, 02:00 PM   #150
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That's interesting. Can you please tell me what motor wind you run and if you have tried gearing differently when comparing the 2 packs ?
sphere comp/Novak 10.5 24/78 in my 2wd buggy. This is going by the finger. both packs weight adjusted too.
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