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Old 02-12-2011, 03:27 PM   #16
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Gillblade how many ppl u know have gone 100mph with rc car?
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Old 02-12-2011, 03:35 PM   #17
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Yes, there are definitely going to need to be some extreme mods in all areas to get to 100mph.

One thing to look at is the sheer amount of power it takes. When you get up to those speeds air resistance and friction become a huge factor. Look at real 1:1 cars, a car with a 150HP motor might go 120mph, but a car with a 300HP motor (double horsepower) is not going to go 240mph, for that you'd need like 1000HP! Power does not scale linearly in this case, it is exponential. In terms of an RC car it might take a 20W increase in power to go from 15mph to 30mph, but to go from 60mph to 75mph it might take a 100W increase. Both increases were only 15mph, but the faster one took 5 times as much power.

All those numbers are just examples, probably not accurate, but the principles are. You will need some heavy duty power to hit 100mph, and that's just one aspect of it. Keeping the car on the road is another challenge altogether!
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Old 02-12-2011, 03:47 PM   #18
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Someone correct me if I'm wrong but I believe it states on castles website that the 5700 is the fastest out of all of them. I have the 7700 and 9000
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Old 02-12-2011, 04:00 PM   #19
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Yes, there are definitely going to need to be some extreme mods in all areas to get to 100mph.

One thing to look at is the sheer amount of power it takes. When you get up to those speeds air resistance and friction become a huge factor. Look at real 1:1 cars, a car with a 150HP motor might go 120mph, but a car with a 300HP motor (double horsepower) is not going to go 240mph, for that you'd need like 1000HP! Power does not scale linearly in this case, it is exponential. In terms of an RC car it might take a 20W increase in power to go from 15mph to 30mph, but to go from 60mph to 75mph it might take a 100W increase. Both increases were only 15mph, but the faster one took 5 times as much power.

All those numbers are just examples, probably not accurate, but the principles are. You will need some heavy duty power to hit 100mph, and that's just one aspect of it. Keeping the car on the road is another challenge altogether!
Yep. Aerodynamic theory suggests a cubed function, speed to the 3rd power as far as power requirements, based on simple shapes. 8 times as much power to go twice as fast. In practice it is typically different, usually worse, with a car (RC or real) due to the rather complicated overall shape, wheel wells and such. At different speeds the vortexes move and cause different secondary effects. That’s also why a body that provides downforce at 40 might fly at 80 or whatever for example.
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Old 02-12-2011, 04:12 PM   #20
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Someone correct me if I'm wrong but I believe it states on castles website that the 5700 is the fastest out of all of them. I have the 7700 and 9000
A Castle (or any brand) 540-size motor is not going to be up to the challenge, regardless of the kv rating. Simply not enough torque and power. You could try to gear for 100mph but it wouldn't get there, the motor would overheat and fry. For something like this you are looking at 4S+ lipo and a 15-series Neu/Castle, or Tekin buggy motor. Even with that it will be a challenge.
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Old 02-13-2011, 08:22 AM   #21
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Gillblade how many ppl u know have gone 100mph with rc car?
3ppl as far as i know here in sweden... Im just wondering WHY go 100mph with a Traxxas Rustler. There are alot more chassies suitable for going 100mph. The rustler may be a nice bashcar, but it aint no aerodynamic wonder. its gonna be hard to keep it on the ground
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Old 02-13-2011, 03:27 PM   #22
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I guess that is the point, it isn't an easy task to do it with a rustler. Why do it if wasn't a challenge? Winning an A final wouldn't mean much to you if it was piss easy..... you enjoy taking on a challenge and succeeding.

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3ppl as far as i know here in sweden... Im just wondering WHY go 100mph with a Traxxas Rustler. There are alot more chassies suitable for going 100mph. The rustler may be a nice bashcar, but it aint no aerodynamic wonder. its gonna be hard to keep it on the ground
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Old 02-13-2011, 05:27 PM   #23
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I agree, not everything needs to have a reason or be practical. It can be done just because you think it is a cool project or fun challenge to take on. I think water-cooling an RC car is a really cool concept, but I also realize it's not necessary or even that practical. I still would like to do it at some point just for the challenge and experimentation.

A lot of projects like this are an evolution. It might start out by adding a higher kv motor to a stock vehicle, or 3S lipo instead of 2S, and then the next thing you know you are looking at redesigning the whole suspension, or creating a custom aerodynamic body.
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Old 01-10-2012, 03:21 PM   #24
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there are plenty of us doing this with rustlers in the united states.
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