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Old 11-27-2008, 12:01 AM   #196
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Originally Posted by Danny/SMC View Post
It's 2 cells in paralell. We hope by having less capacity that the mod guys won't be able to use 2.5 , 3.5 motors and make runtime. So if they have to use 4.5 and up it will slow them down.
Surely if you don't do it someone else will? The only way to slow the cars down is to limit capacity or motors in the rules. In the meantime wouldn't larger capacity speed up the switching process? I would think if you could do a 1 cell pack that can go head to head with 4 cell nimh with the hot motors more people will make the switch, then you can regulate from there.

Thats just my take tho
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Old 11-27-2008, 12:05 AM   #197
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We wouldn't need rules to regulate how much speed and power we have if we would just back off the trigger.
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Old 11-27-2008, 07:13 AM   #198
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Danny, I think this is an awesome idea! Since the pack is 2 cells would you be able to split it for us t-bar guys?!?
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Old 11-27-2008, 08:09 AM   #199
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Originally Posted by miller tyme View Post
Try this, it's a trick used sometimes in modified, for those times when the Rx browns out from voltage dips.

Place a single 1.2v 800mah or similar small cell in series with the red wire from the speed control to the Rx. Charge it as a single cell and when the speedo is turned on it will complete the circuit and put out ~3.7 volts from the internal bec +1.2 from the single cell in series, giving you about 4.9v and only 1 switch. Since there is only the single source connector to the Rx and not another in parrell the ESC will not even know the other cell is there and will not use it to run the motor or charge the battery
I might have to get with you on this. I think David Lee was doing something like this. I can vision it, I just have a hard time with the plumbing, to make it easy to change out and charge would be the key. Interesting....
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Old 11-27-2008, 03:07 PM   #200
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I might have to get with you on this. I think David Lee was doing something like this. I can vision it, I just have a hard time with the plumbing, to make it easy to change out and charge would be the key. Interesting....
Provided it works, put it in the middle of an extension from the speedo plug to the rx. It would be easy to pull out then and you could have one for each heat
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Old 11-27-2008, 03:28 PM   #201
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Surely if you don't do it someone else will? The only way to slow the cars down is to limit capacity or motors in the rules. In the meantime wouldn't larger capacity speed up the switching process? I would think if you could do a 1 cell pack that can go head to head with 4 cell nimh with the hot motors more people will make the switch, then you can regulate from there.

Thats just my take tho
If we can get a battery size rule it should limit the capacity for everyone. I think you'll still se some pretty big motors with 4000 mAh but the speeds (and tire wear) should be more reasonable.
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Old 11-27-2008, 05:27 PM   #202
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Nitro guys have been using 2S lipos for a couple years now. So no, it doesn't cause any issues with receivers and servos.

Paul
they also run 6 volt regulators as well. I know the spectrum receivers can handle the 7.4 volts but most servos are only spec'd up to 6 volts.
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Old 11-27-2008, 07:45 PM   #203
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250 mah being used leads me to believe that the pack was doing a good deal more than what a typical RX pack would. I believe 60ish mah is typical.
That's what I thought too, so that's why I posted it. I'm pretty sure we ran it with the switch on (LRP), but it seemed to run the same both ways. They did try it on Wednesday with the red wire out again, and this time it "worked", but did get the dumpy feeling after 5min.

So far, the only known flawless way to run this 3.7V battery for the full 8 minutes without a performance dropoff is with a GTB, all wires intact on the rx plug, and the switch turned off --thanks KHoff. We'll try it this exact way with an LRP on Saturday and report the results (because last time we tried it, the switch was on and it dumped a lot from the Rx pack). We'll get one of the guys who is running a SpeedPassion to try it as well.
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Old 11-28-2008, 06:17 AM   #204
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hey guys i have been runnning the lipo pack for a couple of days now. it runs awesome. i used a ppd billet lipo tray thing and just cutted it down to fit into the car. i was just wondering what you guys have been gearing them at. i don't run alot of stock, we mainly run 10.5 so i don't have a 17.5 to base the speed of it.

thanks JB Catricala
Hey JB, what's going on?!?! Think you could do me a small favour? If you've got a t-bar car lying around could you see if the pack fits across the chassis above the t-bar without interfering with the shock? I'm going to try and stop when I'm home. See you then, say hi to your folks for me!
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Old 11-28-2008, 09:50 PM   #205
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That's what I thought too, so that's why I posted it. I'm pretty sure we ran it with the switch on (LRP), but it seemed to run the same both ways. They did try it on Wednesday with the red wire out again, and this time it "worked", but did get the dumpy feeling after 5min.

So far, the only known flawless way to run this 3.7V battery for the full 8 minutes without a performance dropoff is with a GTB, all wires intact on the rx plug, and the switch turned off --thanks KHoff. We'll try it this exact way with an LRP on Saturday and report the results (because last time we tried it, the switch was on and it dumped a lot from the Rx pack). We'll get one of the guys who is running a SpeedPassion to try it as well.

When you tested it first and it worked with a reciever pack but drained it that shouldn't be a problem as you can use a bigger mAh pack as the weight of the single cell Lipo is very low so adding a bit bigger reciever pack shouldn't be to much of an issue.
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Old 11-28-2008, 10:03 PM   #206
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Originally Posted by adam lancia View Post
Hey JB, what's going on?!?! Think you could do me a small favour? If you've got a t-bar car lying around could you see if the pack fits across the chassis above the t-bar without interfering with the shock? I'm going to try and stop when I'm home. See you then, say hi to your folks for me!
For T-Plate cars I think the pack will fit on one side of the T-Plate and you just put your electronis on they other side.
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Old 11-28-2008, 11:00 PM   #207
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Originally Posted by adam lancia View Post
Hey JB, what's going on?!?! Think you could do me a small favour? If you've got a t-bar car lying around could you see if the pack fits across the chassis above the t-bar without interfering with the shock? I'm going to try and stop when I'm home. See you then, say hi to your folks for me!
hey adam long no see. umm.... i actually don't have a t-bar anymore, wish i did. Aswell unfortantly it is offroad this week so not alot of 12 scales out. but i don't see why it wouldn't fit. it would probably fit on a car with side dampers, not a friction plate. You will have to play with the shock as well. hope this kind of helps i will check later in next week when more 12 scales come out.

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Old 11-29-2008, 04:54 AM   #208
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When you tested it first and it worked with a reciever pack but drained it that shouldn't be a problem as you can use a bigger mAh pack as the weight of the single cell Lipo is very low so adding a bit bigger reciever pack shouldn't be to much of an issue.
SHOUDN'T BE A PROPLEM!!!!! Where did the extra mAH go. If the RX and Servo only pull what they need then that means the rest went into the ESC, to most likely back-feed to the motor/main battery. No matter how you look at it that's an unfair/illegal advantage and not a practical way to test the likely hood that this set-up would work in competition!
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Old 11-29-2008, 08:16 AM   #209
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Yeah.. That sucks and doesn't need to happen. Mahs just disappearing sounds like bullshit and makes for bad first impressions. Stuff like that needs to be figured out to a T before this thing has any chance of being accepted.

To start, what if you plugged the receiver pack into the receiver and turned it on. Then WITHOUT the main battery plugged in run the throttle on your radio. If the motor wants to roll over, that would tell me that the receiver pack is bleeding over to the power side. If that happens, try something else.

This damn thing just may not work until we have a specific built speed control. Then we would have no strings attached, I know everyone loves a little black magic, but cheating is cheating.

I heard someone say cut the racing time down. There's no way cutting races back down to 6 minutes is going to fly, 8 minutes is part of what makes the racing great.
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Old 11-29-2008, 11:52 AM   #210
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I'm sure that speed control manufacturers will do the proper changes for this to work perfectly. It just takes some time but it will happen. In the meantime it seems like the GTB works in this application so if one ones to run this with no issues just run a GTB.
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