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Old 11-08-2013, 07:18 PM   #1
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Default 6S for lst2 xxl

I just got a maxamp 5450mah 120c for my lst2 e conversion. Still learning about the whole battery set up. Havent fried one yet in 7 years but now im pushing big power. The cc1717 in my lst2 xxl e is all new from the 1520 and I don't want to screw anything up. Any help greatly app.
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Old 11-08-2013, 07:58 PM   #2
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the losi will easily handle that set up and the 1717 in it will make it a BEAST!!!! losi is a pretty simple conversion just be sure to go with tdr conversion and not losi's
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Old 11-08-2013, 08:00 PM   #3
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+1 for TDR parts. They are extremely high quality and make Losi's conversion look like a toy
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Old 11-08-2013, 10:29 PM   #4
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Smile Battery

Ive had the truck built now for two years. Im just rebuilding it maintaining it adding some new parts and the new 1717. I was running the neu castle 1520 on 6s for the life of the truck. Thing is the "c" rating was only 25c on battery I was running with that motor. What is the big difference in 25c-120c?
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Old 11-08-2013, 11:34 PM   #5
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The stream of electrons can move with lesser resitance.

This means:

Less friction and reduced heating of the battery.

Better throttle response as the motor can suck the juice out the battery faster.
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Old 11-09-2013, 06:38 AM   #6
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The higher the c rating the less internal resistance of the battery, generally speaking. It is also linked to the capacity of the battery which makes the internal resistance highly variable between different capacity batteries. On top of that, manufacturers have their own way of rating a battery. You mentioned 25c ? brand/capacity and 120c 5450mah maxamp.

Lets just say for example the 25c has a capacity of 4500mah. The c rating is more than likely a constant draw capability (amps). The calculation is - 25c*4.5ah=112.5 amps. This means the cells should hold a minimum of 3.7v under a load of 112amps. It can peak at higher amps but the internal resistance will play a much bigger part and it's almost impossible to make accurate calculations given all the variables as well as those variables will change with heat (from use) and capacity remaining.

The maxamp c rating is more than likely a maximum/peak current draw possible from the pack (obviously fresh off the charger). 120c*5.5ah=660amps peak current draw for a limited number of seconds. In my experience I have never seen any pack even come close to putting out 600amps. To make matters worse they don't even give a constant current rating so you don't really know what the pack is capable of in relation to the one above.
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Old 11-09-2013, 07:50 AM   #7
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I notice a lot of Losi owners are using Castle...any use Tekin's RX8 and motor combo? Or am I missing something that Losi's like CC's better.
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Old 11-09-2013, 09:28 AM   #8
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I am using a RX8 ESC in my XXL, and that works perfect!
I think that te reason is that Castle a bit cheaper is to buy, and they are good products?
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Old 11-09-2013, 01:04 PM   #9
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Quote:
Originally Posted by SUNA View Post
I notice a lot of Losi owners are using Castle...any use Tekin's RX8 and motor combo? Or am I missing something that Losi's like CC's better.
LST's are big trucks and bigger motors compliment them better. Castle used to have motors (1518, 1520, 1717) that are bigger than Tekin's motors. Those Castle motors and other big motors from Leopard are sensorless so there's really no need to spend more for the Tekin that's able to run sensored as well as sensorless. But you can if you want.

PinkPanda basically summed up the c-rating question but it's good to point out that c ratings are more of a guide than fact. If you took a 5000mah pack rated for 25c continuous it should be able to put out 125amps continuously. But that is not the case. If you draw 100amps from that pack continuously for more than a few seconds damage will occur. There are videos on YouTube where people test the c rating of a pack and none survive when the amp draw is anywhere near what the c rating suggests it should be able to take. Put a 100amp load on that 5000mah 25c pack will be overheated and in thermal runaway in around 30 seconds. Even though a 1/8 system may draw 100amps it's only for a fraction of a second and the average draw is closer to 75amps. That's why everything survives in the real world.

Maxamps rating system just confuses things further. Don't be fooled, they're playing the hype game with seriously inflated ratings to try and justify their price.
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Old 11-09-2013, 07:29 PM   #10
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Default max amp infalated price

Thanks guys for the info. Ill probably go back and read that a few times. Until I completely understand amps and all that. I just always play it safe and never let things get hot.
Did I buy a bad battery? Should I return it and get a thunder pack? Or a Venom. I just want a good reputable battery beyond turnigy nano...etc

Again thanks, I ve got two builds going on right now hopefully I can get some pic's up soon
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Old 11-09-2013, 08:34 PM   #11
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I wouldn't say you bought a bad battery, maybe overpaid a bit for what it is. I haven't had any of their packs from recent years but I wasn't impressed then and from what I've seen they haven't improved enough (if at all) to warrant the price. There are other brands with the same quality for less and not just Turnigy. I've never had Nano's but I do run the standard 30-40c 5000mah in my 1717 powered LST XXL and it's great, no problem keeping up. If you don't mind spending some dough Hyperions are a better battery than Maxamps and a little cheaper. I never should be sold the Hyperions I had. From what I've seen Venom Lipos really can't handle higher draw 1/8 systems very well. They're ok in a buggy if you keep the speeds down, but a truck like my nephew's 1515 powered LST puffs Venoms even geared for about 40mph. Btw I have personal experience with 3 Venoms I bought on sale and seen many others at the lhs dead. I've tried removing the dead cells but I've rearranged 3 venom packs and all repuffed on the first run. Polyquest/Enerland Lipos are also a great quality pack for a good price. I don't have much first hand experience with other brands.
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