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Old 07-19-2007, 12:27 PM   #121
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If that small amount of voltage difference is so important, why is it people running 5 cells are so happy?
http://www.rctech.net/forum/showthread.php?t=173028
If they are having such good luck running 5 cell, what is the problem running lipo with its' weight savings? I'm going to go reread that thread.
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Old 07-19-2007, 01:18 PM   #122
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It's pretty clear that there are certain people in certain segments of racing that may want to stay with NiMH until something changes, like weight rules. That's okay, it's not a knock on LiPo. If anything, we should feel sorry for those guys, because they're excluded from something that really restores some joy to racing by removing one of the biggest headaches. And unlike motor tuning, I don't ever hear anybody say they love the rigors of NiMH maintenance, so it's not like anybody would be sad to see it go.

You guys aren't liberated by the voltage of NiMH, you're trapped by it. Think about that for a minute. Everywhere you look, people are asking questions about LiPo, getting excited about it, and praising it for how much simpler it makes things. And you guys don't get to play, peeking out from behind your monstrous GFX's and discharge trays, agonizing over every .01V you lose, and watching your batteries decline with every single cycle. Bummer. And I mean it, that sucks for you guys.
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Old 07-19-2007, 01:26 PM   #123
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The way I see it, The 4200's has a slight advantage on power so It should not be an issue if some racers who want to go to lipo as long as thier car makes the minimum weight..... IMO atleast......

The advantage of going to lipo imo is the consistency of the battery over a long period of time...........................
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Old 07-19-2007, 01:40 PM   #124
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What I'm having trouble deciding, is whether or not voltage means as much with brushless motors, and I mean the slower ones, like stock. I truly don't see the gap between LiPo and NiMH when we're all running 13.5's, and it's not like the guys I'm racing with are using busted old batteries.
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Old 07-19-2007, 01:44 PM   #125
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Also, I'm not convinced the voltage difference between NiMH and LiPo on a discharger tells the whole story. On the track, the packs seem to have more punch out of the turns, especially after the first couple of laps when the NiMH fades a bit. Are other contributing factors, like lower IR helping? I have a hard time believing a 4800 LiPo performs worse on the track than a 3800, or old 4200. I just haven't seen it, not even close. When I ditched my aging 4200's for LiPo, the performance increase was noticeable immediately.
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Old 07-19-2007, 01:46 PM   #126
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Quote:
Originally Posted by Francis M. View Post
The way I see it, The 4200's has a slight advantage on power so It should not be an issue if some racers who want to go to lipo as long as thier car makes the minimum weight..... IMO atleast......

The advantage of going to lipo imo is the consistency of the battery over a long period of time...........................
I totally agree. That's the argument actually being used against LiPo now. Nominal voltage definitely doesn't tell the whole story.
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Old 07-19-2007, 02:01 PM   #127
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Quote:
Originally Posted by Francis M. View Post
The way I see it, The 4200's has a slight advantage on power so It should not be an issue if some racers who want to go to lipo as long as thier car makes the minimum weight..... IMO atleast......

The advantage of going to lipo imo is the consistency of the battery over a long period of time...........................
This statement is dead on the money. Make weight and run it. People really need to get over themselves. NiMh are still getting better voltagewise. Durablity has suffered, but they still continue to get better. If it's such a disadvantage now to run Lipo, let me.

I actually like spending good money once on batteries that I can run for a year or two and they'll never drop off, vent, or dead short. That means I have more money for tires, and have to carry a five gallon bucket less of crap to the track.
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Old 07-20-2007, 07:58 AM   #128
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Quote:
Originally Posted by sportpak View Post
This statement is dead on the money. Make weight and run it. People really need to get over themselves. NiMh are still getting better voltagewise. Durablity has suffered, but they still continue to get better. If it's such a disadvantage now to run Lipo, let me.

I actually like spending good money once on batteries that I can run for a year or two and they'll never drop off, vent, or dead short. That means I have more money for tires, and have to carry a five gallon bucket less of crap to the track.
Yup........
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Old 07-20-2007, 08:24 AM   #129
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Quote:
Originally Posted by syndr0me View Post
When I ditched my aging 4200's for LiPo, the performance increase was noticeable immediately.
I have seen this statement many times and if your packs were that beat, then yeah you would see an immediate improvement. Hell, you would have saw an immediate performance improvement if you had bought new Nimh packs. I think it is not right to compare old worn packs to something new. Just not a good comparison imo. I am glad everyone is happy with their Lipo packs but I am not investing in it untill it becomes mainstream everywhere. Meaning that every big race allows them for use. Until then I will continue to run my Nimh packs until something changes. I can't figure out if this is the wave of the future why are the top pros not pushing to get these packs legal for use everywhere?
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Old 07-20-2007, 08:43 AM   #130
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Quote:
Originally Posted by Yeti35 View Post
I have seen this statement many times and if your packs were that beat, then yeah you would see an immediate improvement. Hell, you would have saw an immediate performance improvement if you had bought new Nimh packs. I think it is not right to compare old worn packs to something new. Just not a good comparison imo. I am glad everyone is happy with their Lipo packs but I am not investing in it untill it becomes mainstream everywhere. Meaning that every big race allows them for use. Until then I will continue to run my Nimh packs until something changes. I can't figure out if this is the wave of the future why are the top pros not pushing to get these packs legal for use everywhere?


I don't really care if the pros use it or not. I beleive that most people are not looking to LIPO for a performance advantage but more for its longevity and ease of maintenance. These 4200's are great on the track but they need constant baby sitting during, in between, and after races.
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Old 07-20-2007, 08:47 AM   #131
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This toy reminds me of the Current NIMH on the market. lol




The Tamagotchi (たまごっち) is a handheld digital pet created in 1996 by Aki Maita and sold by Bandai. The Tamagotchi is housed in a small and simple egg-shaped computer. Three buttons (A, B, and C) allow the user to select and perform an activity, including:

Feeding the Tamagotchi a piece of food or a snack.
Playing a game with the Tamagotchi.
Cleaning up a Tamagotchi's messes.
Checking its age, discipline, hunger, weight, and happiness levels.
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so much for "not equivalent" voltages between nimh/lipo-778px-tamagotchi_0124_ubt.jpg  
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Old 07-20-2007, 09:00 AM   #132
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Quote:
Originally Posted by Francis M. View Post
This toy reminds me of the Current NIMH on the market.
Someone made the analogy once that NiMH are like a nest of chirping baby birds, always requiring attention. It's by far my favorite. :-)

Yeti: That's understandable, it's a safe bet to wait. If I attend big races, I'll buy two new fresh NiMH packs too. In the meantime, though, LiPo generally does its thing for club racing without the hassles of NiMH maintenance. Yea, it cost me $70 for a charger, and $150 for two packs, but I can almost use those indefinitely. I guess what I'm trying to say is that LiPo can offer a nice respite from NiMH between those few big races each year, ya know?

It's true, my cells were tired. But they definitely weren't a year old, more like 3-4 months of regular use. And I always bought the good stuff (SMC) with higher voltage intended for stock. I -definitely- didn't feel like I came out flat switching to the LiPo. I shared that mostly in response to someone saying they performed like year old 4200's. That was not my experience at all, though I wouldn't doubt that new NiMH packs would have felt good too. My LiPo still feel that good, though, and it's been a while now. :-)
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Old 07-20-2007, 09:14 AM   #133
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As for NiMh vs Li-Po, I have ran both in my Type-R with the following results.

Running 13.5 on carpet with foams:

With NiMh I would slow a couple tenths an the end of a race.
With Li-Po I would not fade at the end of the race at all.
With NiMh I was a couple tenths faster at the beginning but gave it back at the end.

Mind you running very good SMC IB4200s.

Now with my Type-R and Li-Po, running it under weight it was slower then the car with NiMh. But when the car was brought back up to weight and balanced out it is now faster then NiMh.


Later,
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