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Old 12-16-2008, 03:12 PM   #616
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Originally Posted by kn7671 View Post
I agree

Regarding LiPo, I don't think 1s 3.7v LiPo is the solution. Why do we want to make this more complicated that it already is. With a 1s LiPo, you have to run a receiver pack, alter the setups, run different motors, different tires, etc.... This "SIMPLE" 1s 3.7v LiPo is becoming more costly by the day. Now we here that some ESC's won't function well at 3.7v.

If the day comes that we have to dump NiMh batteries for one reason or another, than a 7.4v LiPo and 21.5 motor would be the better choice. All of the electronics work better at the higher voltage, it is simpler to wire up, and the weight will still be lighter than the current 4-cell NiMh setup.

Best post I've read on this thread! I agree 110%. 7.4v Lipo and 21.5 motor for stock and 7.4v 17.5 superstock. Let's keep it simple with just two classes. Done!

BTW here is the pack I'm running. Super cheap, 10-15 minute run time, no dumping feeling, faster servo response, no receiver pack, no cutting esc wire, no low voltage booster. Also it will fit t-bar


http://www.cheapbatterypacks.com/mai...an=ELT&cat=ELA
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Old 12-16-2008, 03:17 PM   #617
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Best post I've read on this thread! I agree 110%. 7.4v Lipo and 21.5 motor for stock and 7.4v 17.5 superstock. Let's keep it simple with just two classes. Done!

BTW here is the pack I'm running. Super cheap, 10-15 minute run time, no dumping feeling, faster servo response, no receiver pack, no cutting esc wire, no low voltage booster. Also it will fit t-bar


http://www.cheapbatterypacks.com/mai...an=ELT&cat=ELA
If we must go to Lipo, then I would vote for this as well. This way the only thing I have to buy is another motor, and a battery pack.
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Old 12-16-2008, 04:22 PM   #618
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To the people saying 7.4v 21.5 will be about the same speed as 4 cell 17.5, have any of you tried it yet? I only ask because I have not, but to me it seems like it would still be significantly faster than 4 cell 17.5. I have not yet done any lipo testing but intend to in the near future. To me, 3.7 seems like the better way to get lipos in 1/12 scale.
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Old 12-16-2008, 04:41 PM   #619
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The Future of 1/12 will just be more of the same only more expensive IE:
Brushless will level the field and be cheaper in the long run: Bull $#!t
New speedo, new motor,about $300, now the latest speedo with programing, another $200, the start of the motor wars all over again with the release of the Pulse another $60 (problems aside you know it begins) so were at least talking another motor.

In the last year I would have only gone through 3-5 brushed motors= $175 plus about $50 in bulk brushes, and could have bought them over time and if needed to replace only spent about $35. Latest and greatest advancement would have been a motor not a speedo and motor.

No matter what rules change, what technology develops, the fast people who tinker with their stuff and buy the latest will still be the fast people the rest will just pull the car out of the box with the motor and battery still in as it had been for the last race and still wonder why the can't win.

Now that said I'm not completely anti brushless, just a realist who fully expects Li-po to invade 1/12, and I fully expect it to change nothing other than to cost more money and allow the less than energetic people not to have to put as much time into a HOBBY.
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Old 12-16-2008, 05:09 PM   #620
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The Future of 1/12 will just be more of the same only more expensive IE:
Brushless will level the field and be cheaper in the long run: Bull $#!t
New speedo, new motor,about $300, now the latest speedo with programing, another $200, the start of the motor wars all over again with the release of the Pulse another $60 (problems aside you know it begins) so were at least talking another motor.

In the last year I would have only gone through 3-5 brushed motors= $175 plus about $50 in bulk brushes, and could have bought them over time and if needed to replace only spent about $35. Latest and greatest advancement would have been a motor not a speedo and motor.

No matter what rules change, what technology develops, the fast people who tinker with their stuff and buy the latest will still be the fast people the rest will just pull the car out of the box with the motor and battery still in as it had been for the last race and still wonder why the can't win.

Now that said I'm not completely anti brushless, just a realist who fully expects Li-po to invade 1/12, and I fully expect it to change nothing other than to cost more money and allow the less than energetic people not to have to put as much time into a HOBBY.
Mr. Miller, I have tried to tell people this for a long time, but no one listens, except us veterans who have been down this road before. Brushless was made roar standard so that people like Bob Novak could make even more money. When lipo comes out, the battery wars will begin again. Hell, for that matter, It's almost started now. Heating pads, who's got the hot battery this week, it's like running NiMH, only on a much more expensive scale. The ONLY advantage I see is that we won't have to buy batteries as often, which will make them even more expensive. Yup, brushless and lipo will save the hobby, and make many of us with empty wallets and a budget worse off.
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Old 12-16-2008, 05:17 PM   #621
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Originally Posted by MUDVAYNE View Post
Mr. Miller, I have tried to tell people this for a long time, but no one listens, except us veterans who have been down this road before. Brushless was made roar standard so that people like Bob Novak could make even more money. When lipo comes out, the battery wars will begin again. Hell, for that matter, It's almost started now. Heating pads, who's got the hot battery this week, it's like running NiMH, only on a much more expensive scale. The ONLY advantage I see is that we won't have to buy batteries as often, which will make them even more expensive. Yup, brushless and lipo will save the hobby, and make many of us with empty wallets and a budget worse off.
For those of you who must buy a battery each week to get your speed this is the way it may be. The battery is not what makes you faster.
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Old 12-16-2008, 05:23 PM   #622
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The ONLY advantage I see is that we won't have to buy batteries as often, which will make them even more expensive.
I have batteries that are a year old and run just as well as the newly purchased batteries and I paid less than I paid for matched Nimh batteries.

You also sound like your trying to say that RC hasn't been expensive to begin with.....
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Old 12-16-2008, 05:57 PM   #623
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For those of you who must buy a battery each week to get your speed this is the way it may be. The battery is not what makes you faster.
Example A: club racer at a bigger race against sponsored drivers who can drive a carbon copy line every time....agreed the best batteries in the world won't matter.

Example B: 2 local club drivers of similar driving ability, in a local points season or bragging rights race, one driver buys the latest infinity-C rated battery and has more punch and run time and likely wins, next week the other guy buys one also, then brand x battery makes another improvement or a new charger comes out, and it all begins again.

Locally there is a racer of average Club ability who has gone through about 10 lipo packs trying to keep up with the latest including special packs for VTA, another for 1/12, that's less than I've spent on NiMh and I can reconfigure them for any car.

Lipo will be just as expensive, and if a cell goes bad it will be a total loss at the price roughly 3 times that of a NiMH.
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Old 12-16-2008, 06:00 PM   #624
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For those of you who must buy a battery each week to get your speed this is the way it may be. The battery is not what makes you faster.
No Karl, set-up, learning to drive a better line, and learning to wrench on your stuff is makes you faster., I haven't had to buy batteries in 6 months.

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Originally Posted by EVILGRAFX View Post
I have batteries that are a year old and run just as well as the newly purchased batteries and I paid less than I paid for matched Nimh batteries.

You also sound like your trying to say that RC hasn't been expensive to begin with.....
I have heard from a national champion that he gets a new lipo every month because they can't take the abuse a NiMH battery can. He has said that they fall off 3 or 4 tenths, where as NiMH won't do that. But, since he is sponsered, he runs what is given to him.
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Old 12-16-2008, 07:38 PM   #625
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Everyone always says it is about driving, but when a new go fast item comes out, there is a line at the LHS, or tracks hobby shop and they sell out FAST!

Everyone is always trying to gain an advantage, their driving isn't what matters, or at least as much if they just bought the best battery money can buy. That is what most think, or it wouldn't happen over and over.

Imo, set up is the single most important factor. Batteries are only important if your not finishing, or your driving flawlessly lap after lap and your only a few tenths off from worst to best lap, but still a half second off the pace.

Then buy a better battery.

If your best lap is a 14.4 and your worst is a 23.8 and your average is a 16.0 a battery or faster brushless set up, is a waste of money.

14.4 to 15.0 and maybe a bobble lap at 15.4.....then I can see an upgrade being important.

Just my thoughts, even though I haven't run 1/12th in a while.


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Old 12-16-2008, 07:51 PM   #626
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Here are a few numbers to consider:

17.5 = 2200 KV
4 round cells @35 amps
4.8 X 2200 = 10560 rpm

21.5 = 1800 KV
2s lipo
7.4 X 1800 = 13320 rpm
( I would bet that the lipo would be more than 3.7 volts per cell @ 35 amps so rpms would be higher)

A-123's with 21.5
@35 amps
5.6 X 1800 = 10080 rpm

A-123's with 17.5
5.6 X 2200 = 12320 rpm

I like the rpm's with 123's, very close to the 4 round cells.......BB
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Old 12-16-2008, 08:17 PM   #627
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That's just another thing to go wrong and be tampered with.

I still believe that 2s (7.4V) lipo and low Kv motors are the way to go from an efficiency stand point. I can see smaller motors being introduced in the future, but not now. I would like to stay away from reciever packs as much as possible.

-Frank
That is true there is more possibility for tampering. But if you do it right it should be fine. The same was said about rebuildable stock motors as well. So long as the regulator is inside the sealed hard case then any tampering would be evident as it would cause damage to the case.
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Old 12-16-2008, 08:40 PM   #628
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Originally Posted by MUDVAYNE View Post
I have heard from a national champion that he gets a new lipo every month because they can't take the abuse a NiMH battery can. He has said that they fall off 3 or 4 tenths, where as NiMH won't do that. But, since he is sponsered, he runs what is given to him.
Thats crap (no offence). I've been running the same lipos in my TC for 6 months and I'm still as quick as ever. Running cost is way down compared to NiMH and the convenience is worth every cent extra I paid for the battery pack, which is already offset by the need for less packs and no equalising/discharging gear.

Lipo is coming because it's a superior technology
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Old 12-16-2008, 08:47 PM   #629
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Buggy Brad probably has one of the best arguments so far. Why has no one talked about using A123 cells. They us a much safer Lithium technology and provide slightly lower voltage which would make the 21.5 motor a viable solution. The only change would be how to mount the cells in the car with there size. Airplanes have been using these cells for some time so all the technology is there.

Here's a link to a flying website I found with a comparison someone put together when A123 cells where probably be considered for airplanes. It may be old but it gives a decent baseline to compare each battery technology.

www.flyelectric.ukgateway.net/lithium-a123.htm
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Old 12-16-2008, 08:51 PM   #630
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they dont exactly fit in our cars ....
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