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Old 08-27-2011, 12:04 PM   #2971
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I'm not doubting that your 5800 is faster for you, but it's not due to C rating.

In comparing one battery to another (for simplicity sake compare a 6000 of the same brand to a 4500 in the same brand) the biggest reason you think the car is faster is because the voltage drop off on the 6000 is less than on the 4500 because your using less of the battery's overall capacity and staying in the higher voltage range longer.

hope this helps.
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Old 08-27-2011, 12:22 PM   #2972
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In comparing one battery to another (for simplicity sake compare a 6000 of the same brand to a 4500 in the same brand) the biggest reason you think the car is faster is because the voltage drop off on the 6000 is less than on the 4500 because your using less of the battery's overall capacity and staying in the higher voltage range longer.

hope this helps.
That's my point.

My response to kinga was due to him bringing up the calculated max amperage delivery, which is pretty well pointless for "spec" classes. A real hot mod setup might stress the battery, and C ratings would then become more important.
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Old 08-27-2011, 01:16 PM   #2973
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Anyone have a link to some Titanium screw kits for the t32011? Also the ball studs too!
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Old 08-27-2011, 06:46 PM   #2974
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Originally Posted by rx7ttlm View Post
In comparing one battery to another (for simplicity sake compare a 6000 of the same brand to a 4500 in the same brand) the biggest reason you think the car is faster is because the voltage drop off on the 6000 is less than on the 4500 because your using less of the battery's overall capacity and staying in the higher voltage range longer.

hope this helps.
That is the reason the car is faster on the last few laps of the race. There is less voltage drop, so the car is faster.
I am not sure of the argument for a lower capacity battery like 40c, when I am under weight with a high cap 60c batt, that delivers higher voltage for longer, why would I go to a 40c batt?
Not starting argument or anything, just interested in the theory behind it.
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Old 08-27-2011, 06:59 PM   #2975
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That is the reason the car is faster on the last few laps of the race. There is less voltage drop, so the car is faster.
I am not sure of the argument for a lower capacity battery like 40c, when I am under weight with a high cap 60c batt, that delivers higher voltage for longer, why would I go to a 40c batt?
Not starting argument or anything, just interested in the theory behind it.
No argument, just seems your terminology is confused.

More mAh = More Capacity

Higher C rating = Higher Voltage under load, so theoretically MORE amperage delivery while maintaining minimum safe voltage

The point is, yes, a higher capacity pack will come off after a run with a higher voltage, so the power drop off [all other things equal] will be less toward the end of a run.

BUT, as long as your C rating is high enough to be suitable for the application, it no longer matters.

The clearest analogy I can think of quickly: it's like your kitchen sink. At full flow, let's say it delivers 2 gallons per minute. If you're filling a swimming pool, it's probably not the best choice, as it would take forever. If you're filling a shot glass, you don't need to [and probably wouldn't] open the faucet full, as most of the water you're using would just go down the drain.

So, if you think of water flow as battery C ratings, and a shot glass is a 17.5 Blinky setup, you don't need anything drastic. If the swimming pool were a hot mod setup, you'd want a fire hydrant, with the biggest hose connection you could find.
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Old 08-27-2011, 07:13 PM   #2976
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ahh k i see. IT seems that high c rating and high MAH rating go hand in hand these days. I havent seen too much around under the 60c lately
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Old 08-27-2011, 07:18 PM   #2977
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ahh k i see. IT seems that high c rating and high MAH rating go hand in hand these days. I havent seen too much around under the 60c lately
That's true, which means just about any legal battery is suitable for spec classes; capacity, weight and price are more important than the C rating.
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Old 08-27-2011, 11:13 PM   #2978
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Tp4200 packs stand for Thunderpower 4200 packs ! Most racers run 17.5 or 13.5 so that's why I suggested tp4200 40c packs(less than $99) , and might solve your weight problems if you already owned heavy expensive parts and electronics !!!! I agree with running 6000mah 60c packs if you can make weight, but I don't agree on throwing away standard servos, heavy electronics, steel screws, regular bodies, etc...,to save weight, when you can lose more weight by buying your next battery pack carefully !!!! It would have cost me at least $1000 to buy all these upgrades for my four+ tc4's just to compete ! One $85 tp3200 40c for stock , and one $99 tp4200 40c for mod solved my problems !!!!! By the way my Mod car only burns 2300mah after 6minutes .....
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Old 08-27-2011, 11:26 PM   #2979
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I also run against others running 65c packs with boost , and I they have no punch or top speed advantage over my tp4200 40c in a 6minute main ! I also run a Gtb 3.5t with no lipo cutoff !!!! If only I could drive as good as they do....
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Old 08-27-2011, 11:34 PM   #2980
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If your buying packs just get the 65 c packs unless you have an aversion to it(for race packs). The packs will outlast your motors and cars if your buying Thunder power packs. I have packs from 2 years ago that are still runnable. Call around, there are some shops that sell the 65c packs for 109. In that time most people move up to mod... then you have happy mod packs too. Anything over 50C is fine for most of this toy game anyhow. Keep in mind however that one company's 65c pack isn't directly comparable to anothers since there isn't standardization in the testing practices as I know.

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I also run against others running 65c packs with boost , and I they have no punch or top speed advantage over my tp4200 40c in a 6minute main ! I also run a Gtb 3.5t with no lipo cutoff !!!! If only I could drive as good as they do....
Unless your racing at MACH I would probably suggest trying a 4.0 or 4.5 till your driving can take it. I have a 3.5, tested with it. Put it back in the box and it hasn't come back out lol. Silly power but there was no way I could be consistent with it. Just a thought...
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Old 08-27-2011, 11:44 PM   #2981
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I totally understand about the 3.5t speed, but I like the challenge ! I have another tc4 with a novak hv4.5 at 4s to practice smooth driving with a much faster car !!!! The learning curve is incredible and fun ....
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Old 08-28-2011, 06:22 AM   #2982
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Why are we talking about a TC4 on the T3'11 thread?

We got started on this whole battery thing because some guys are having issues making weight.

I have an RC4 PT, JR DS8717 full size servo, micro DSM2 RX, Tekin RS Pro, D3 17.5, motor guard, Protek 5000mAh 50c, run a regular weight P37R body, I have to add 60g to make 1380g, and my car is balanced. All of my ballast weight is under the front belt, on centerline, and I've corner weighted my car on scales, coming out to 25% each wheel.

As you can see, I don't go crazy on light weight items, and if I happen to run somewhere that uses a spec tire [I usually mount my own with lightweight inserts], I can remove weight, without affecting balance, and still get down to the minimum.

So, the moral of the story, IMO, is to pay attention to the weight of the battery when you buy! There's no need for $200 batteries in a spec class. I run boosted, so there's a bit more load on the battery, but my battery has also been run with good results in mod.
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Old 08-28-2011, 09:06 AM   #2983
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Hi everybody!
I would like to' ask if do you all have an idea if xray will release 2012 Model for the coming season!?

Tanks!!!
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Old 08-28-2011, 09:38 AM   #2984
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Hi everybody!
I would like to' ask if do you all have an idea if xray will release 2012 Model for the coming season!?

Tanks!!!


Based on previous experience, they always do. Usually unveil in/around October, available in the States November on the first order run, Christmas time or after if you don't get in on the first order.

What's it going to have? Usually minor updates, and nobody knows for sure. The speculation is having the servo rotated 90 degrees, gear diff and spool, and the newest vertical ball stud diff clamps.

Yes, they usually sell conversion kits to update the previous year's model.

And nobody can tell you if it's worth waiting or not, because it's really up to you and what you want.
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Old 08-28-2011, 11:14 AM   #2985
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I have an RC4 PT, JR DS8717 full size servo, micro DSM2 RX, Tekin RS Pro, D3 17.5, motor guard, Protek 5000mAh 50c, run a regular weight P37R body, I have to add 60g to make 1380g...
Have you checked this on more than one scale?
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