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Old 12-17-2008, 09:09 AM   #646
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I dont know about "at least double" with the run time answer, but you are correct, they do last longer then comparable NiMh cells.
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Old 12-17-2008, 09:16 AM   #647
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There's always an excuse. Your batteries were no good. LiPo magically has more mAh that what they're rated for. Have fun dumping if you run a 3000 mAh 2 cell pack in mod. That is unless you plan on running at 13.5 or 10.5 speeds for 8 minutes.

And a new chassis plate to run A123 cells (that aren't legal at a ROAR race)? Are you kidding me? There's no need to add anything other than a receiver pack and a LiPo pack to change the battery out from NiMh. I've done it and that's all you need.

Any change that doesn't let me go back to NiMh for big races is not a good option as far as I'm concerned. That means no major changes to the car like new pod or main chassis.

We can go back and forth all day about this and it's not going to convince me that the testing that I've done at the track is wrong. Go test whatever you guys want but have fun converting your car back to NiMh for a big race.
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Old 12-17-2008, 09:26 AM   #648
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There's always an excuse. Your batteries were no good. LiPo magically has more mAh that what they're rated for. Have fun dumping if you run a 3000 mAh 2 cell pack in mod. That is unless you plan on running at 13.5 or 10.5 speeds for 8 minutes.

And a new chassis plate to run A123 cells (that aren't legal at a ROAR race)? Are you kidding me? There's no need to add anything other than a receiver pack and a LiPo pack to change the battery out from NiMh. I've done it and that's all you need.

Any change that doesn't let me go back to NiMh for big races is not a good option as far as I'm concerned. That means no major changes to the car like new pod or main chassis.

We can go back and forth all day about this and it's not going to convince me that the testing that I've done at the track is wrong. Go test whatever you guys want but have fun converting your car back to NiMh for a big race.
Who the /// I like this guy! Keep it real Unregistered.
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Old 12-17-2008, 10:00 AM   #649
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There's always an excuse. Your batteries were no good. LiPo magically has more mAh that what they're rated for. Have fun dumping if you run a 3000 mAh 2 cell pack in mod. That is unless you plan on running at 13.5 or 10.5 speeds for 8 minutes.

And a new chassis plate to run A123 cells (that aren't legal at a ROAR race)? Are you kidding me? There's no need to add anything other than a receiver pack and a LiPo pack to change the battery out from NiMh. I've done it and that's all you need.

Any change that doesn't let me go back to NiMh for big races is not a good option as far as I'm concerned. That means no major changes to the car like new pod or main chassis.

We can go back and forth all day about this and it's not going to convince me that the testing that I've done at the track is wrong. Go test whatever you guys want but have fun converting your car back to NiMh for a big race.
I don't change anything to run 4 cell and A-123, I can run one then the other back to back. It's seems that A-123 systems has no interest in being ROAR approved they seem to be in the full size electric car market. I wish that ROAR would grab a few packs and perform there tests so they would be legal. I had long discussions with the ROAR officials at this years 1/8 on-road nats about 123's.....BB
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Old 12-17-2008, 10:07 AM   #650
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There's no need to add anything other than a receiver pack and a LiPo pack to change the battery out from NiMh. I've done it and that's all you need.
I think you forgot that a person would need a motor also, I run 13.5 and if I went to 1 cell lipo I would need to buy a 10.5 to run in the same class......BB
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Old 12-17-2008, 11:12 AM   #651
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So u have a123's in a 12th car,,
Yes and no, while not A123 cells specificly the same cell construction. Pics of them in my hyperdrive pro3

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Old 12-17-2008, 11:25 AM   #652
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I've done some testing with those same LiFePO4 cells. Probably a good option for t-bar cars but if you go with 2s-2p they only have about 2000 mAh and would be pretty hard to make time in mod. That being said, they would have about 4000 mAh as 1s-4p and that should be doable for mod.

I agree with Unregistered that whatever we do it needs to make sense for stock, superstock and MOD.
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Old 12-17-2008, 11:33 AM   #653
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I've done some testing with those same LiFePO4 cells. Probably a good option for t-bar cars but if you go with 2s-2p they only have about 2000 mAh and would be pretty hard to make time in mod. That being said, they would have about 4000 mAh as 1s-4p and that should be doable for mod.

I agree with Unregistered that whatever we do it needs to make sense for stock, superstock and MOD.
Yep runntime is a prob as I could'nt make 8mins with a 17.5, how would you construct a 1s-4p?
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Old 12-17-2008, 11:58 AM   #654
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Just connect all of the neg ends together to one solder tab/connector and then all of the pos ends together to the other tab. It takes two jumper wires over the shock instead of two. Then you should make time with 17.5 and 13.5's but I suspect that with these cells you'll go flat at the end as the voltage trails off.
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Old 12-17-2008, 12:05 PM   #655
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Thanks I'll try that and see what the results are.
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Old 12-17-2008, 12:08 PM   #656
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With single cell voltage and a 17.5 you'll need a huge rollout (like 4.0" or so) and it's slower than 17.5 4 cell. With a 13.5 you'll be pretty close to where a 17.5 4 cell rolls out at (3.25 or more). 13.5 single cell is close to 17.5 4 cell speeds on the track.
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Old 12-17-2008, 12:27 PM   #657
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I have a better idea, how about the people who like lipos can go and run the new li//bl pro pan car class and the people who like nicds & brushed motors can go and run 1/12th scale. Two years from now we will see which one prevails and I already know which one will. The 10.5 spec class will allow for battery wars, but I doubt 99% of the average racers will see an improvement in lap times since they already go 50+ mph
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Old 12-17-2008, 01:04 PM   #658
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id run both of those classes ...
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Old 12-17-2008, 01:11 PM   #659
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I have a better idea, how about the people who like lipos can go and run the new li//bl pro pan car class and the people who like nicds & brushed motors can go and run 1/12th scale. Two years from now we will see which one prevails and I already know which one will. The 10.5 spec class will allow for battery wars, but I doubt 99% of the average racers will see an improvement in lap times since they already go 50+ mph
Great idea, but at my track everybody has a WGT car but nobody runs them. Might have somthing to do with the spec (3700) pack they put in there but not sure.

Out of 12 cars (1/12) last fri all but 2 I think were brushless. 2 were 13.5/1s, the rest were 17.5/4 cell. Brushed motors are on there way out (thankfully) and soon the ni-mh will be too. But it will hang on I think the longest in 1/12 seeing how old the class is. The WGT and Pro10 guys are already pushing for 2s.

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Old 12-17-2008, 02:05 PM   #660
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Look - 3.7v LiPo is not sensible since it will require the use of a Receiver Pack. That means that another battery on our cars, and another battery that will need to be ROAR approved, thus raising the cost again. Most people are turning to 1/12 racing from Sedan racing as a way to race at reduced cost, but now we are wanting to increase the cost again.

This is so simple, it is slapping us around. Keep NiMh for now, then transition to a 7.4v LiPo. If this is too fast for the "Stock" crowd, drop down to a 21.5 motor, as gearing will be very close to a 17.5 motor running 4-cell NiMh.
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