The World's Fastest Off-the-Shelf RC Car Can Hit 100 MPH

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rohitbaran

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[citation][nom]sbuckler[/nom]I bet it also does 100 to 0, $1100 to 0, and 1 car to 1000 tiny pieces in 0.001 seconds - the first time you crash it into something solid.[/citation]
My thoughts exactly. To run it safely, you need a pretty long track without obstacles.
 

STravis

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[citation][nom]geekapproved[/nom]High performance brakes???RC cards do NOT have brakes at all.[/citation]

Actually they do. How do you think Nitro powered vehicles stop? And if they exist on Nitro, it's not that big a deal to put them on Electric ones (assuming you don't want to rely on the motor to stop the car)
 

alidan

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been looking for a good cheap 1/36 i believe scale ec car for playing around with in my house, an rc race track made of cement, a hill (stairs with some cardboard over it) and a track made of old videogame cartrages cases and cardboard would be a pretty fun time, but not 100$ worth of fun...

also looking for a small cheap helicopter thats better than the cheap airhogs ones, where you can only really control how high it flys and the moment you can make it hover, is the moment you run out of things to do.
 

ricdiculus

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[citation][nom]geekapproved[/nom]High performance brakes???RC cards do NOT have brakes at all.[/citation]

While there are no mechanical brakes on ELECTRIC cars, there speed controllers use regenerative braking. By using the motor as a generator, the load creates resistance to rotation and thus creates braking force. Gas cars (at least mine) have little baby disc brake rotor and pads.
 

utgardaloki

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[citation][nom]__-_-_-__[/nom]10 seconds battery life?[/citation]

High performance electrics use high performance lithium polymer (Lipo) batteries. These batteries have much higher capacity than traditional ones like nickel-cadmium or metal-hydride. Plus they have incredible power outputs. Traditionally there has been no point in outfitting battery dependent machines with rediculously powerful electric motors since there were simply no batteries even remotely capable of suporting them. It's only very resently (last 7-8 years) that altogether new kinds of battery technologies and batteries were developed.
The rc helicopter I described above typically use two 5000 mAh Lipo batteries in series. The most powerful kind of those batteries right now (goes up every year) can output about 15 000 watts continiously and about 30 000 watts (650 amps at 45 volts) in shorter bursts without overheating. These particular batteries weigh no more than 1600 grams. That's insane tradionally speaking. A typical family car uses about 35 000 watts while cruising at 60 Mph. The car and pay load weighs in at about 2 tons. The heli at about five kilos.
The power output of these particular batteries is enough to completly fry your typical stove and oven all at the same time (typical stove and oven all on highest = 5000 watts).

If you gear an electric rc machine in a certain maner and strangle it as much as possible by programming the electrical speed controller (ESC) you can get the machine to "only" output combustion engine level power. If you do that a typical high performance electric rc machine can beat the running time of a combustion counter part by quite a lot. I know of contest racing electric rc cars that can run for as much as 40-60 minutes on one charge as long as you don't accelerate to fast and too often (a personal vehicle with even less power can run for hours). So yes... this car will beat the 10 second streak.

But one of the main reasons people today go for electric in rc isn't because of the possibility of longer running times. It's mainly because of the insane power levels. It's potentially not a little more powerful than combustion like let's say 30-50 persent but rather several hundred percent more powerful. That and the minor maintenance work needed compared to combustion.


[citation][nom]geekapproved[/nom]High performance brakes???RC cards do NOT have brakes at all.[/citation]

Rc cars (especially combustion versions) often use mechanical brakes. Many electric rc cars how ever use the ESC to brake. The ESC simply reverses the current at the same time as it changes "output" mode to "input". The motor thus becomes a generator instead of a motor. In other words, when you break you will at the same time charge the batteries. The harder you "brake", the faster the ESC will allow the back flow current to trickle into the battery making it essentially harder for the motor to spin and the wheels to turn.

For personal vehicles there really isn't much use for this power yet even though technically it is possible. There is no point in building a car with several thousend horsepowers (yeah that's right) using electric motors as long as current batteries will be drained in about 10 minutes if you constantly use it.

Still holding my breath for newer battery technologies.
 

buzznut

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[citation][nom]cdburner5911[/nom]really? kilovolts? Am I getting my units wrong, or are you implying it has a 1.65 million volt motor? Perhaps try watts instead.[/citation]
kV would be 1000V. MV is MegaVolts. So yes, you are getting your units wrong.
 

livebriand

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Just beware - with speeds like that, you will likely run it into something, thus damaging the car. I have an rc one that goes to 30mph or so and have damaged stuff several times.
 

walter87

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[citation][nom]sbuckler[/nom]I bet it also does 100 to 0, $1100 to 0, and 1 car to 1000 tiny pieces in 0.001 seconds - the first time you crash it into something solid.[/citation]
I want to see what would happen to one of these if it hits a pebble on the road going full speed :)
 

Trex 700

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There are rc helicopters that will do 105mph upside down and backwards...AND can go from 83 mph to zero in a few feet. (it looks like 1 foot but it's hard to tell when there is no reference point in the sky).

They are spiking 10,000 watts during the most aggressive moves.
 
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