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Old 11-13-2016, 08:27 PM   #1
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Default shorty for TC (T3 car) and F1, to save buying twice lipos?

Hi, rather new to the hobby so looking for some guidance. I've done a search and read what people have to say regarding using a shorty lipo vs normal for TC... There seems to be arguments for both sides of the fence, but I think the general gists of it is- as long as you have sufficient Mah in the shorty, it should do the job just as well.


- I have a Xray T2 and T3 and want to do some races (likely in our 17.5 stock class which run 5 min races on a pretty small twisty track).

- As well as that i want to race in the F1 class which use a 21.5T motor with 10 min races.

If i buy a good shorty pack of at least 4000+mah (i.e. 4200-4700) would this fill the job for both cars/ races? Most guys run around 6000+ Mah in the TC class but as the races are only 5 mins would a 4000+Mah shorty be sufficient or have a serious competitive disadvantage? How many batteries would i need to race this (would 4 be sufficient)?

As the T2 and T3 chassis's are made for normal size lipo's, would taping in a shorty lipo (in the middle of where the normal lipo would go) have any serious negative handle effects?

Any tips to save buying double the batteries would be cool.


Thanks!
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Old 11-13-2016, 10:20 PM   #2
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You shouldn't need more than 2 batteries per class you run, and can usually get away with just 1. I'd start with getting 2 shorties, use 1 per car. If you're not happy with the performance of the shorty in the TC, then get 1 or 2 full size batteries.

There will be 2 main disadvantages to using a shorty in the T3. The first is that in stock classes, higher mAh is often better as the voltage drop towards the end of the run can hurt. It's not usually a massive drop, but if you're competing at the top level, it can make a difference. If you're new to the hobby like me, I wouldn't worry about it. I actually find the voltage drop helps get better lap times due to improved driving lines. Once you get better at driving you'll be able to make better use of better equipment. The other disadvantage is that it might be too light, so you'll need to add lead weight to maintain a good left/right balance, or move the ESC to the battery side.
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Old 11-14-2016, 02:07 AM   #3
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Quote:
Originally Posted by gigaplex View Post
You shouldn't need more than 2 batteries per class you run, and can usually get away with just 1. I'd start with getting 2 shorties, use 1 per car. If you're not happy with the performance of the shorty in the TC, then get 1 or 2 full size batteries.

There will be 2 main disadvantages to using a shorty in the T3. The first is that in stock classes, higher mAh is often better as the voltage drop towards the end of the run can hurt. It's not usually a massive drop, but if you're competing at the top level, it can make a difference. If you're new to the hobby like me, I wouldn't worry about it. I actually find the voltage drop helps get better lap times due to improved driving lines. Once you get better at driving you'll be able to make better use of better equipment. The other disadvantage is that it might be too light, so you'll need to add lead weight to maintain a good left/right balance, or move the ESC to the battery side.

thanks for the input.. yeah i'm new to rc so i wont be running at the very front (based on driving alone), but at the same time I don't want to unnecessarily disadvantage myself...

Your idea sounds sensible with the 2+ shorty packs. And I'll try find the larger mah shorty packs (are there any shorty's above 5000mah?).. Also how long between using a lipo do you need to let it cool before you can charge it again (i.e. if I'm impatient and want to charge it after a run so i can get back out there asap again).

Would sticky taping in the shorty to what is visually the middle of the battery deck be any concern?

I assume if I'm underweight , then adding lead would still be an advantage over a heavier battery as i could then chose where to mount it to balance the car (lower CG).

Thanks!
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Old 11-14-2016, 08:34 AM   #4
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One battery pack that works perfect everywhere is near impossible to find, but you'll need to give up the extra mah to make it work. A fantom 5000+mah shorty lipo will work great in your case...
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Old 11-14-2016, 11:32 AM   #5
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The real question is, "Are you going to be running both classes on the same night/racing event?" If you are then get a new and decent (inexpensive) battery for each car. There usually isn't enough time between heats and/or rounds to recharge batteries AND swap them between cars.

I would also consider getting a battery charger that can balance charge 2 batteries at the same time. Again a decent battery charger doesn't have to be expensive either.

If you currently only have a single battery charger, then you might consider getting 2 batteries for each car, or even 3 batteries total and just swap them in and out between charges/heats.

If I was just starting out, I would spend money to make sure I have a good used or new chassis before worrying about the best of everything else. You will want to save money for the parts you may break.
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Old 11-14-2016, 06:06 PM   #6
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I use a shorty in my T3 rubber edition, added hudy weights in the tray which lowers the CG. Also added a hudy 30g weight under the belt just in front of the motor and a couple of 20g in front and behind the battery.
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Old 11-14-2016, 10:17 PM   #7
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Quote:
Originally Posted by MaxRain View Post
I use a shorty in my T3 rubber edition, added hudy weights in the tray which lowers the CG. Also added a hudy 30g weight under the belt just in front of the motor and a couple of 20g in front and behind the battery.
cool how does it run? Why did you choose to run the shorty and what shorty are you running? Noticeable performance drop over a normal lipo with higher mah for you?

thanks to the others for your input... The fantom 5000+mah sounds worth looking at.

But also maybe you're right having one new good battery per car would be best (then just have a couple of okay/ used ones for practice). Cheers for the tips on the charger.
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