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Old 05-21-2014, 03:37 AM   #31
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Originally Posted by TB03Racer09 View Post
wow, lots of great info, keep it going

The chassis I plan to start racing with is a Tamiya TB04 Pro V2, which is a heavy car compared to all the double deck belt drives. I kind of understand why almost everyone is using big 6000mah+ LiPo's, better have more battery than more lead weight.
I would consider a High rated C shorty pack to try to negate the higher weight of the chassis, do you have any battery rules?

I don't know the dimensions of your battery area but this might be an option.

http://www.hobbyking.com/hobbyking/s...arehouse_.html

Hope that helps!

It will need charging after every race, they appear to be good value for the money.
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Old 05-21-2014, 05:55 AM   #32
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We run the 6 min. qualifiers and 8 or 15 min. mains in USGT. The shorty pack helps with the balance but just doesn't have the mah to stay in the flat of the voltage curve for the long mains. We also run the USGT weight rule of 1450g. The big battery with no ballast is right there and equal left to right. Front to rear is a little off but not much with a VBC D05.
80c helps also.
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Old 05-21-2014, 09:42 AM   #33
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My Son and I tried the shorty route in our TC, 17.5 and 13.5.
I have to say that the Lap times in 17.5 were better in the beginning of the run, but increased drastically towards the end of the race. In 13.5 I had an advantage only in the infield, but not enough strait line speed. We ran the new Trinity 5000mA pack.
Now we went back to the normal sized packs and the lap times are more consistend through the race in 17.5 and definitely faster in 13.5.
BTW the internal resistance is much better in normal sized lipos than in shorts.
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Old 08-18-2014, 08:14 PM   #34
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I currently have a 9t motor using a 5000mah pack thats 330gm or so. Going down to a 2200mah pack would shave off 200gm, would there be much performance gain (cornering etc) in the car with a low turn motor? I understand play time would be less but I wouldn't mind getting 2 packs.
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Old 08-18-2014, 10:47 PM   #35
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I currently have a 9t motor using a 5000mah pack thats 330gm or so. Going down to a 2200mah pack would shave off 200gm, would there be much performance gain (cornering etc) in the car with a low turn motor? I understand play time would be less but I wouldn't mind getting 2 packs.
are you running round cells? my 5000mah lipo weighs under 275 grams and my 6000 mah lipo weighs 300grams
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Old 08-19-2014, 12:12 AM   #36
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are you running round cells? my 5000mah lipo weighs under 275 grams and my 6000 mah lipo weighs 300grams
currently using a 2s hardcase (330gm). I was going to consider a shorty that would be about 200gm. I'm just wondering if say a 130gm difference, then a relocation of the ESC in front of it would see noticeable gains in laptimes. The question is it ultimately worth the $35 mod?

Seems like 2200 may be too less for a 9T motor (10min< run times would suck).
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Old 08-19-2014, 12:25 AM   #37
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Like goots said, 330g seems quite heavy for a 5000mah, unless it's with dean's and pigtails I suppose. I also didn't realize batteries as small as 2200mah were available. Anyway, that's all besides the point. If a battery's current output is proportional to it's capacity, then the 2200mah may provide a weak discharge rate compared to the 5000. That all depends the the "C" rating or internal resistance. With a 9T you should be able to feel the difference between a 20C and a 60C, for example. How this relates to laptimes, that depends on your driving. Of course, shaving weight will improve a car's performance, all else equal. But changing a pack eliminates the "all else equal" part, so it's a consideration of numerous elements.
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Old 08-19-2014, 12:45 AM   #38
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Like goots said, 330g seems quite heavy for a 5000mah, unless it's with dean's and pigtails I suppose. I also didn't realize batteries as small as 2200mah were available. Anyway, that's all besides the point. If a battery's current output is proportional to it's capacity, then the 2200mah may provide a weak discharge rate compared to the 5000. That all depends the the "C" rating or internal resistance. With a 9T you should be able to feel the difference between a 20C and a 60C, for example. How this relates to laptimes, that depends on your driving. Of course, shaving weight will improve a car's performance, all else equal. But changing a pack eliminates the "all else equal" part, so it's a consideration of numerous elements.
yeah it seems like the 2200mah is out of the question. There's a shorty on HK that's got a discharge of 65-130c (my 5000mah has a 40c discharge) so I guess that changes the comparison as well..

I guess it's something I'll need to test and find out
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Old 08-19-2014, 02:11 AM   #39
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Originally Posted by Djchow85 View Post
yeah it seems like the 2200mah is out of the question. There's a shorty on HK that's got a discharge of 65-130c (my 5000mah has a 40c discharge) so I guess that changes the comparison as well..

I guess it's something I'll need to test and find out
If you decide to try the HK nano tech shorty packs, go for the A-spec nano techs, they are rated the same C, but are noticeably more punchy than the "normal" nano tech's.
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Old 08-19-2014, 12:22 PM   #40
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http://www.tqrcracing.com/shop/produ....asp?p_id=6352

These are, imo, the best batteries on the market. I run them in my 17.5 car. I've got two of them, and one of them is 315.8g and the other is 316.3g. Absolutely the best batteries I've run. I charge them full, run them for long long times and then stick em back on the charger back to back and after 6 months of using them, they're still flat as a board.

I can run the exact same lap times at the start of a pack as I can at the end of 6 mins, and even coming up to 10min, I'm only .1-.2 off my pace, and I'm one of the faster stock drivers at my local track.

I personally think you need as much capacity as possible in Stock. You want that curve to stay up as long as it can to supply you the most amount of power for 5-6mins. Mod is different because the car actually gets easier to drive as the voltage drops and you can go faster with less voltage because it's less puncy. Stock? More is better!
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Old 05-02-2016, 12:24 PM   #41
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Hi Guys

I also need help in picking the right lipo for my 17.5 Blinky racing.

We do 2x 5min Qualifiers & 1 Final of 5 min.

We have a medium size track with a small straight of about 20 meters, the rest is turns a technical parts.

I've weighted my electronics.
Servo - 40g
ESC - 85g
Motor - 180g
Add 15g for wires

Total = 320g

This is the batteries I own.
Xpower 3900mah - 40c = 230g
Xpower 3400mah - 25c = 195g
Turnigy A-Tech Nano 6200mah - 65c - 130c = 310g
Gens Competition 7200mah - 70c = 325g

My chassis will be the 3Racing Sakura XI Sport(Stock settings)

What will be my best battery for my application?

Thanks
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