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Old 04-09-2008, 07:10 AM   #1
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Default why the RC continues to be at 7V

With newer battery like lifepo4 and lipo

why the RC continues to be at 7V ?

the newer powertool is now 18 to 36V with better power and run time

at this level the wire is to much small and less heat

I dream to have open competion voltage

I thinks Roar made good ahead with lipo but the limit of 7.4V and 7.2V is the past
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Old 04-09-2008, 07:20 AM   #2
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With newer battery like lifepo4 and lipo

why the RC continues to be at 7V ?

the newer powertool is now 18 to 36V with better power and run time

at this level the wire is to much small and less heat

I dream to have open competion voltage

I thinks Roar made good ahead with lipo but the limit of 7.4V and 7.2V is the past



For sure, I mean I only get 30min. of runtime with un-controlable power in my B44.

If ROAR would allow 22.2Volt packs I could spend three times as much on a battery!!!



P.S. shouldn't you be in school?
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Old 04-09-2008, 07:26 AM   #3
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There is nothing wrong with the current batteries we are using now.
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Old 04-09-2008, 07:56 AM   #4
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They will catch one one day. Trying to explain to this folks that HV is better is like teaching old dogs new tricks. If you want some advice from folks that are playing with HV, please look for info here: www.rc-monster.com/forum.
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Old 04-09-2008, 08:00 AM   #5
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There is nothing wrong with the current batteries we are using now.
I agree, Can't wait to come up to your track !!! What inserts & tires are working there truck,2wd,4wd ??
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Old 04-09-2008, 08:00 AM   #6
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Keep it as it is now, already way to much power with LIPO/Brushless.
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Old 04-09-2008, 08:01 AM   #7
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They will catch one one day. Trying to explain to this folks that HV is better is like teaching old dogs new tricks. If you want some advice from folks that are playing with HV, please look for info here: www.rc-monster.com/forum.
I have no problem with HV batteries. Come to my track any day and put 36V in your car. Let's see what happens...

I'll even use 7.2V with my 13.5.
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Old 04-09-2008, 08:05 AM   #8
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yes i see old school

easy the people search better IR more C rating

but with HV 18 awg cable and less is very good

the IR of the plug is negligible only need good 10A cell

don't need 10 mosfet in ESC to reach good 10A power 200watt with one fet or 6 for brushless

a small quark22A is OK to power 1/10 scale at this V & A
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Old 04-09-2008, 08:24 AM   #9
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simple question of space
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Old 04-09-2008, 08:39 AM   #10
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no need more space

lifepo4 in SC cell 22 X 43mm

or lipo take any form factor

you don't need 4.5T motor but 25 or 30T

low KV motor like 1600KV for same power than any 8.5t
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Old 04-09-2008, 08:41 AM   #11
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power=amps*voltage=watts. A 7.4volt 5ah pack will deliver 37watt hours of power. A 22volt 1.6ah pack will deliver 37watt hours of power. You use the same size packs, they are just wired differently. When you lower the amperage resistance is less of a factor & things become more effecient. It is not an matter of wanting more power, instead it is a matter of using a setup that will last longer. However, I will agree that it is hard to argue w/ batt & motor//esc combos that will last you a year w/out replacement.
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Old 04-09-2008, 09:05 AM   #12
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What is the problem with the current 7.4 volt lipo batteries? Is the 14 awg wire needed in off-road to large and expensive? Is 7.4 not fast enough? Is a 4.5 turn brushless motor too slow?

What is the problem with current stuff that everybody should replace their Electronic Speed Control, Motor, Batteries, Charger, and Power Supply for?

What would the advantage be that would be worth spending the amount of money it would take to replace all that?

Some day, new dogs become old dogs and learn that there are no tricks, just education and experience.
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Old 04-09-2008, 09:06 AM   #13
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HV is catching on the emerging 1/8 electrics. Many are running 6s lipos and lower KV motors to keep things nice and cool for really long run times. The demand for this is prompting the Mamba Monster Max, Quark, Tekin, and other mfgs to make ESCs for higher voltage.

1/10 cars don't seem to have the same overheating issues that the 1/8's do, so the need for HV just really isn't there. Most 1/10s run very well on 6 or 7 cell nimhs or 2 cell lipos. Someone might want to try a lower kv motor on 3s though for really really long run times. I can get 45 minutes out of my 3s 8000 pack in my Rusty VXL geared to the moon, so if the motor was a lower KV more practical for the track, I probabyl could run well more than 1 hour 1:15 straight with no problems and practically no heat.

The other issue is cost and availability of charging equipment. Higher volt batteries are not cheap. The market is heading in that direction, but it will take some time.
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Old 04-09-2008, 09:16 AM   #14
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A 6kmah 11.1volt pack will cost the same as a 8kmah 7.4volt pack. As temperature increases resistance increases & eff. decreases. The last time I checked you want eff. to increase.
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Old 04-09-2008, 09:28 AM   #15
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Quote:
Originally Posted by foolio View Post
I have no problem with HV batteries. Come to my track any day and put 36V in your car. Let's see what happens...

I'll even use 7.2V with my 13.5.
HV application is better for larger scale vehicles. For 1/10th scale 3S should be good and that's what I run some of my cars. I don't have time to race, but you could see a huge benefit from going up to 3S lipos. One of those benefits would be less AMP draw. As you know AMP causes heat and heat makes any set up less efficient. You could makes a much power with your 13.5 with 3S lipos as the guy using a lower turn motor (8.5), but you would be using less AMPs and your motor and ESC would be creating less heat. You might even be able to run a 20 to 30 minute main. It's just simple math.
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