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Old 11-04-2008, 10:30 AM   #256
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Originally Posted by Roland S View Post
Hi, Steve:

Let me introduce you Donny Lia, the current IIC 1/12 Stock A-Main winner, the track/hobby shop owner at http://www.360rcspeedway.com/ I’m going to use his lap time to compare so people can see how the 2-cell set up perform. On the current layout, people would do 10.1, 10 flat, better driver do 9.8, occasionally 9.7 and they would finish with a low 47 laps or high 48 laps. One Friday night, I and Donny did a mid 49 laps. We both were doing more 9.7 and 9.6 and a few 9.5. I’m not trying to compare my driving to Donny’s driving; I’m a decent driver, but certainly my line wasn’t as clean as Donny’s, but the speed of Monba’s 5400kv with 1.7” tire and 88/16 gear ratios definitely help.
Roland not trying to stir anything but you really have to compare apples to apples. If you are trying to get a setup close to 17.5/4-Cell stock, you really need to run a 17.5/4-Cell setup in your car, with your driving, to baseline your (Roland's) lap times. Then switch back to your 2-cell Lipo setup and see what you get. I've just noticed that since you've been messing with the 2-cell lipo setup I've never seen your car look comparable to stock speeds, it is always alot faster (19T or even Mod looking) ie- That Friday night you are speaking of, your car went down the straightaway with what looked like to me mod speeds or at the very least, 10.5 speed, whereas I was running 17.5/4-cell.

I think the 2 cell idea can be a great one too, I just want to help you get it so that the speeds are more comparable in case we do go that route.

Thanks, and great job with the testing so far.
-Donny

ps-Thanks for the plug!
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Old 11-04-2008, 11:31 AM   #257
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I could go with single cell with a voltage booster...that would be static and not be nearly the hassle of a reciever pack. If the future went that way I could even envision the booster being built into the ESC. I would still like to see a smaller motor but that would be further down the road.
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Old 11-04-2008, 11:54 AM   #258
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Can someone explain to me what exactly the hassle of a rx pack is? I know lots of guys that run them (nitro guys) and it seems to me that you charge it up once in a while and go play. What's the big deal?
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Old 11-04-2008, 12:33 PM   #259
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For a lot of us, a simple receiver pack isn't a big deal. For others, it is.

A simple voltage booster is probably a better idea for most classes because it's a no brainer. Turn on the switch and it goes.
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Old 11-04-2008, 01:30 PM   #260
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If you need reciever packs for 1/12 cars Muchmore has them, they are on the Tower Hobbies website.

Stock numbers:
MMRC2032 250 mah 10C
MMRC2033 300 mah 10C

http://www3.towerhobbies.com/cgi-bin...?&I=LXUDT4&P=7
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Old 11-04-2008, 03:03 PM   #261
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The flight power 350mah 2 c pas is 15 bucks.... not 23+ shipping. all though you would still need a voltage regulator.
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Old 11-04-2008, 03:12 PM   #262
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Quote:
Originally Posted by RC8 View Post
Phhhhtt, one cell? You mean 6 don't you or did you forget about that pesky little Rx pack you have to keep recharging? One more thing to fail. Simple? My ass.

How do figure it's not balanced? Do you know the exact mass of each component? I'd think twice before you speak so freely about something that you so seemingly have no clue about.

And as far as it looks, don't be hatin'!
read into it what you may RC8,
my flight pack in my 10r5 doesnt need recharging but once a month if i dare to let it go that far ...
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Old 11-04-2008, 04:05 PM   #263
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Quote:
Originally Posted by 360rcspeedway View Post
Roland not trying to stir anything but you really have to compare apples to apples. If you are trying to get a setup close to 17.5/4-Cell stock, you really need to run a 17.5/4-Cell setup in your car, with your driving, to baseline your (Roland's) lap times. Then switch back to your 2-cell Lipo setup and see what you get. I've just noticed that since you've been messing with the 2-cell lipo setup I've never seen your car look comparable to stock speeds, it is always alot faster (19T or even Mod looking) ie- That Friday night you are speaking of, your car went down the straightaway with what looked like to me mod speeds or at the very least, 10.5 speed, whereas I was running 17.5/4-cell.

I think the 2 cell idea can be a great one too, I just want to help you get it so that the speeds are more comparable in case we do go that route.

Thanks, and great job with the testing so far.
-Donny

ps-Thanks for the plug!
Thank you Donny for shedding some light here. It is refreshing to have someone on this thread particularly have an opinion and still manage to be a gentleman. Well played!
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Old 11-04-2008, 04:14 PM   #264
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Originally Posted by reenmachine View Post
Can someone explain to me what exactly the hassle of a rx pack is? I know lots of guys that run them (nitro guys) and it seems to me that you charge it up once in a while and go play. What's the big deal?
I've raced in both electric and nitro over the years with reciever packs. Granted things are probably a bit different now with LiPo RX packs my experiences in the past have soured me on it. Unless you repeak the pack every race along with your main pack you run the risk of it running out partway through the race. It's hard to know how long the pack will actually last without repeaking so if you wait and guess when it needs to be repeaked you run a risk. Then there is the issue of 2 on/off switches...If you remove one of the power wires from the servo harness to disable the BEC you have to turn both switches on for it to work. That is one more switch that could potentially get knocked to the off position in an accident. Conversely if you leave all the servo harness wires plugged in then you have to remember to only turn on the reciever pack, if you turn both on by accident you could fry your reciever. Again another switch that could get turned on in an accident frying your reciever. Additionally it is another component that has to be mounted in the car that could get knocked out in an accident and take you out of the race.

Basically it adds another point of failure which could take you out of the race.
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Old 11-04-2008, 04:17 PM   #265
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There's no hassle with a rx pack. I made a 5 cell AAA 50mAh pack that gets charged at .5amp for about 4-5 minutes before each run. It's no hassle at all and charging the pack is just part of my pre race preperation. You do not need anything like a 350mAh or anything near that type of capacity. About 35mAh is all that is used during a 8 minute run. I have used both a AMB transponder and a PTX and they don't seem to draw anymore current than one another so the 50mAh pack is fine. Cheers, Chris.
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Old 11-04-2008, 04:26 PM   #266
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hey if i use one off those small lipo recerver packes in my 1/12th will i need a regulator aswell or will it be ok
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Old 11-04-2008, 04:28 PM   #267
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use a 6 volt regulator man!
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Old 11-05-2008, 07:39 AM   #268
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Originally Posted by InspGadgt View Post
I've raced in both electric and nitro over the years with reciever packs. Granted things are probably a bit different now with LiPo RX packs my experiences in the past have soured me on it. Unless you repeak the pack every race along with your main pack you run the risk of it running out partway through the race. It's hard to know how long the pack will actually last without repeaking so if you wait and guess when it needs to be repeaked you run a risk. Then there is the issue of 2 on/off switches...If you remove one of the power wires from the servo harness to disable the BEC you have to turn both switches on for it to work. That is one more switch that could potentially get knocked to the off position in an accident. Conversely if you leave all the servo harness wires plugged in then you have to remember to only turn on the reciever pack, if you turn both on by accident you could fry your reciever. Again another switch that could get turned on in an accident frying your reciever. Additionally it is another component that has to be mounted in the car that could get knocked out in an accident and take you out of the race.

Basically it adds another point of failure which could take you out of the race.
Most of us are smart enough to throw a piece of strapping tape over the extra switch so that it doesn't get turned on by mistake (or a turnmarshall). It's a non issue for anyone that has an IQ above room temperature.

Also, it's not a big deal to charge a receiver pack. It's not like we haven't run them before and it's not hard to do. A simple voltage converter is probably going to be the way to go and that won't require any charging. Once we have a booster that works the extra pack argument will be gone for good.

The future of 12th will involve slow change. Not just because the class isn't really broken but because it's a worldwide class. Whatever we do, it must work with both carpet and asphalt. Any changes need to fit into the worldwide rules and not just our little American rules.

Baby steps will change 12th over time but a complete tearup of the rules will completely split up the class worldwide. As soon as we tell Europe and Japan to completely change 12th they're going to tell us to go piss up a rope.
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Old 11-05-2008, 08:22 AM   #269
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I would be very interested in seeing this voltage booster .. if it silison based .. it will most likely fail under load .. (let the magic smoke out) and if it a step up transformer .. it will be cumbersome and where r u gonna put that in an alreadt cramped 12th chassis. Op amps are not reliable , tend to over heat and .. usually explode if not working properly. not a big explosion but more like that of a cap gun. never the less... it will get your attention. I also hope its not integrated into the speedo as i have just purchased a GTB. One of these days im gonna run that damn 12r5..
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Old 11-05-2008, 08:37 AM   #270
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With the exception of the batteries we run EVERYTHING in the car is silicone based for electronics. As long as the inductor is sized properly (among other things) a buck boost isn't complicated or unreliable.
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