4 Cell Sedan Racing
12-30-2004, 01:49 AM
#241
Tech Adept
What about using smaller batteries and motors, keeping the car in 1/10scale but couple hundred grams less? 
MonoTuning
MonoTuning
12-30-2004, 03:02 AM
#242
Re: Re: Re: in answer..
Originally posted by JayBee
True, but I think, if I'm not mistaken, that you just entirely supplemented blownawayig's viewpoint...
- jaybee
True, but I think, if I'm not mistaken, that you just entirely supplemented blownawayig's viewpoint...
- jaybee
where did he say the reasons why the other countries do better! Dude read alittle slower!
Last edited by speedxl; 12-30-2004 at 03:18 AM.
12-30-2004, 06:16 AM
#243
The issue with LiPo cells is how fragile they are. Hard hits could cause internal shorts and shorts result in some pretty spectacular fires. Over discharging really kills LiPo too. You have to set a hard cut off voltage in airplane speed controls to protect the cells. In a car you would accelerate out of a corner and your car would just shut down. Pulling too many amps can cause a thermal runaway in the cells and a fire. Over charging can cause a thermal runaway and a fire. Charging a pack that took a crash the week before can cause a fire.
LiPo cells also require completely different chargers and users that self educate themselves about how dangerous LiPo bats can be. Airplanes guys by the nature of what they do read instructions and are very careful. If they aren't someone can have fingers chopped off, cars get speared by out of control planes and in rare instanced people have died.
R/C cars are not that dangerous. As a result there are lots of R/C car users that don't read instructions and are pretty careless about what they do. These are the guys that would accidentally burn down their houses or full size cars with LiPo's. These are the guys that will delay LiPo cells from getting into cars by 5 years. Manufacturers are just to scared of litigation to put something that requires careful use in the hands of average R/C car guys.
LiPo cells also require completely different chargers and users that self educate themselves about how dangerous LiPo bats can be. Airplanes guys by the nature of what they do read instructions and are very careful. If they aren't someone can have fingers chopped off, cars get speared by out of control planes and in rare instanced people have died.
R/C cars are not that dangerous. As a result there are lots of R/C car users that don't read instructions and are pretty careless about what they do. These are the guys that would accidentally burn down their houses or full size cars with LiPo's. These are the guys that will delay LiPo cells from getting into cars by 5 years. Manufacturers are just to scared of litigation to put something that requires careful use in the hands of average R/C car guys.
12-30-2004, 06:24 AM
#244
Regarding Brushless...I don't know anyone that isn't excited by the possibility of running Brushless motors. The problem is that they are not mature technology yet in our application. Right now there is no drivable Brushless system that is as fast as a open mod brushed motor. Sure a you can get a Hacker and a huge speed control to go as fast but it is not as drivable and will not fit into a lot of current cars.
The limitation is speed controls...specifically FETs that can handle the loads and spikes and can still be purchased at a price that lets manufactures sell speedo's for less than $500.
Its coming. But we wont all be running Brushless for another couple of years or until all the bugs are worked out.
The limitation is speed controls...specifically FETs that can handle the loads and spikes and can still be purchased at a price that lets manufactures sell speedo's for less than $500.
Its coming. But we wont all be running Brushless for another couple of years or until all the bugs are worked out.
12-30-2004, 08:17 AM
#245
How cool would it be to run a 4 cell Associated RC10L3 with a 19T motor. Easy to set up, cheap parts replacment, same electronics, same body, same tires/wheels (adapters req'd), lighter and probably fast as hell and easy to drive. Wow, too cool !
Oh well ................ just day dreaming.
Oh well ................ just day dreaming.
12-30-2004, 08:30 AM
#246
You will want the big tires that we used on pan cars. Narrow tires will be a handful.
12-30-2004, 08:52 AM
#247
Originally posted by jag88
How cool would it be to run a 4 cell Associated RC10L3 with a 19T motor. Easy to set up, cheap parts replacment, same electronics, same body, same tires/wheels (adapters req'd), lighter and probably fast as hell and easy to drive. Wow, too cool !
Oh well ................ just day dreaming.
How cool would it be to run a 4 cell Associated RC10L3 with a 19T motor. Easy to set up, cheap parts replacment, same electronics, same body, same tires/wheels (adapters req'd), lighter and probably fast as hell and easy to drive. Wow, too cool !
Oh well ................ just day dreaming.
12-30-2004, 08:58 AM
#248
Originally posted by speedxl
You have that already! its called oval!
You have that already! its called oval!
How cool would it be to run a 4 cell Associated RC10L3 with a 19T motor. Easy to set up, cheap parts replacment, same electronics, same body, same tires/wheels (adapters req'd), lighter and probably fast as hell and easy to drive. Wow, too cool !
12-30-2004, 09:06 AM
#249
We have been trying to get class going in our state series, 4 cell 19t Pan car with GT bodies ( Foam Tires). It has totally been stillborne. Maybe Speed or Bullfrog can shed some light on it. But the point is, nobody runs it, even when they have the option to.
12-30-2004, 09:15 AM
#250
Re: Isn't this a great country
[i]...hell, I'd race toasters if that was what they raced here. But then, there's the 2 slice, 4 slice and bagel sized issue... [/B]
12-30-2004, 09:26 AM
#251
Originally posted by AdrianM
The issue with LiPo cells is how fragile they are. Hard hits could cause internal shorts and shorts result in some pretty spectacular fires. Over discharging really kills LiPo too. You have to set a hard cut off voltage in airplane speed controls to protect the cells. In a car you would accelerate out of a corner and your car would just shut down. Pulling too many amps can cause a thermal runaway in the cells and a fire. Over charging can cause a thermal runaway and a fire. Charging a pack that took a crash the week before can cause a fire.
LiPo cells also require completely different chargers and users that self educate themselves about how dangerous LiPo bats can be. Airplanes guys by the nature of what they do read instructions and are very careful. If they aren't someone can have fingers chopped off, cars get speared by out of control planes and in rare instanced people have died.
R/C cars are not that dangerous. As a result there are lots of R/C car users that don't read instructions and are pretty careless about what they do. These are the guys that would accidentally burn down their houses or full size cars with LiPo's. These are the guys that will delay LiPo cells from getting into cars by 5 years. Manufacturers are just to scared of litigation to put something that requires careful use in the hands of average R/C car guys.
The issue with LiPo cells is how fragile they are. Hard hits could cause internal shorts and shorts result in some pretty spectacular fires. Over discharging really kills LiPo too. You have to set a hard cut off voltage in airplane speed controls to protect the cells. In a car you would accelerate out of a corner and your car would just shut down. Pulling too many amps can cause a thermal runaway in the cells and a fire. Over charging can cause a thermal runaway and a fire. Charging a pack that took a crash the week before can cause a fire.
LiPo cells also require completely different chargers and users that self educate themselves about how dangerous LiPo bats can be. Airplanes guys by the nature of what they do read instructions and are very careful. If they aren't someone can have fingers chopped off, cars get speared by out of control planes and in rare instanced people have died.
R/C cars are not that dangerous. As a result there are lots of R/C car users that don't read instructions and are pretty careless about what they do. These are the guys that would accidentally burn down their houses or full size cars with LiPo's. These are the guys that will delay LiPo cells from getting into cars by 5 years. Manufacturers are just to scared of litigation to put something that requires careful use in the hands of average R/C car guys.
Regarding LIPO cells. Look at your cell phone and laptop. They seem to charge just fine without fires or explosions. Yes the cells are dangerous, but so are the cell we use. Ironically, at the track last night somebody had a pack that exploded like a gun shot. Once the manufactures or other people figure out high current LIPO cells (they are really close) it will be no more dangerous than the cells we have now.
The charging of LIPO isn't the issue, it's really simple and how you charge your real car battery when it's dead.
Constant amps to a voltage and then constant voltage with the amps falling off to get the capacity. Very simple.
12-30-2004, 09:53 AM
#252
Gotcha...for "Open Mod"
For the other 75-80 percent of us, though...brushless technology is here, affordable and works like a dream.
Let 4300 motors run in stock and you wouldn't have any brushed motors in 2 months...not because the 4300 is more powerful (it's not), but because it's more more fun, reliable and you'd probably end up getting around the track a little faster because you'd have a better race car -- due to the extra laps you'd get in practice.
If someone wants to stick with brushed stuff and think they have an advantage...good for them. The rest of us would have a great alternative that would allow for more fun and less spending/waste.
For the other 75-80 percent of us, though...brushless technology is here, affordable and works like a dream.
Let 4300 motors run in stock and you wouldn't have any brushed motors in 2 months...not because the 4300 is more powerful (it's not), but because it's more more fun, reliable and you'd probably end up getting around the track a little faster because you'd have a better race car -- due to the extra laps you'd get in practice.
If someone wants to stick with brushed stuff and think they have an advantage...good for them. The rest of us would have a great alternative that would allow for more fun and less spending/waste.
Originally posted by AdrianM
Regarding Brushless...I don't know anyone that isn't excited by the possibility of running Brushless motors. The problem is that they are not mature technology yet in our application. Right now there is no drivable Brushless system that is as fast as a open mod brushed motor. Sure a you can get a Hacker and a huge speed control to go as fast but it is not as drivable and will not fit into a lot of current cars.
The limitation is speed controls...specifically FETs that can handle the loads and spikes and can still be purchased at a price that lets manufactures sell speedo's for less than $500.
Its coming. But we wont all be running Brushless for another couple of years or until all the bugs are worked out.
Regarding Brushless...I don't know anyone that isn't excited by the possibility of running Brushless motors. The problem is that they are not mature technology yet in our application. Right now there is no drivable Brushless system that is as fast as a open mod brushed motor. Sure a you can get a Hacker and a huge speed control to go as fast but it is not as drivable and will not fit into a lot of current cars.
The limitation is speed controls...specifically FETs that can handle the loads and spikes and can still be purchased at a price that lets manufactures sell speedo's for less than $500.
Its coming. But we wont all be running Brushless for another couple of years or until all the bugs are worked out.
Last edited by Turbo Joe; 12-30-2004 at 10:08 AM.
12-30-2004, 09:53 AM
#253
Derek - It's not that simple. Cell phone and laptops are made idiot proof. R/C racer will push the cell far beyond phone and laptop use.
Read this thread on R/C Groups to get an idea of what can happen even with careful use of LiPo cells:
http://www.rcgroups.com/forums/showthread.php?t=209187
This is what happen when you overcharge a lipo:
http://www.rcgroups.com/forums/attac...d=130372&stc=1
Read this thread on R/C Groups to get an idea of what can happen even with careful use of LiPo cells:
http://www.rcgroups.com/forums/showthread.php?t=209187
This is what happen when you overcharge a lipo:
http://www.rcgroups.com/forums/attac...d=130372&stc=1
12-30-2004, 10:00 AM
#254
This is an excellent safety video for LiPo use. The key points are always use a LiPo charger and be sure you are using the right settings or this WILL happen:
http://www.helihobby.com/videos/LithiumBattery.wmv
http://www.helihobby.com/videos/LithiumBattery.wmv
12-30-2004, 10:06 AM
#255
Originally posted by Turbo Joe
Gotcha...for "Open Mod"
For the other 75-80 percent of us, though...brushless technology is here, affordable and works like a dream.
Let 4300 motors run in stock and you wouldn't have any brushed motors in 2 months...not because the 4300 is more powerful (it's not), but because it's more more fun, reliable and you'd probably end up getting around the track a little faster because you'd have a better race car -- due to the extra laps you'd get in practice.
If someone wants to stick with brushed stuff and think they have an advantage...good for them. The rest uf us would have a great alternative that would allow for more fun and less spending/waste.
Gotcha...for "Open Mod"
For the other 75-80 percent of us, though...brushless technology is here, affordable and works like a dream.
Let 4300 motors run in stock and you wouldn't have any brushed motors in 2 months...not because the 4300 is more powerful (it's not), but because it's more more fun, reliable and you'd probably end up getting around the track a little faster because you'd have a better race car -- due to the extra laps you'd get in practice.
If someone wants to stick with brushed stuff and think they have an advantage...good for them. The rest uf us would have a great alternative that would allow for more fun and less spending/waste.
