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Old 12-17-2008, 02:17 PM   #661
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I am just curious to see what everyone’s opinion is on the speed of the current STOCK class? Why should we try to "match" what speeds we currently run in Stock just to make a battery change/substitute "acceptable"?

In my opinion I would rather the cars slow down a lot; a lot of people (mainly beginners) now can't handle the stock speeds and as fast as the cars there needs to be 2 separate divisions like nitro races (pro and amateur) in stock just to keep the fast and slow guys happy.

How about we let modified be 'run what you brung' and stock being an entry level class. This lets everyone run what equipment they have and what is ROAR legal, plus now the drivers w/ a high level of talent can finally step up to Mod where there would be a full heat of 10+ instead of just 2 or 3.

What do you guys think?
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Old 12-17-2008, 02:18 PM   #662
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Yes and no, while not A123 cells specificly the same cell construction. Pics of them in my hyperdrive pro3

They seem to fit well, I see they are 30c and if I do the math I come up with 28.5 amps then in a 2p format I get 57 amps. That seems marginal at best, do they feel like they hold there voltage under a load? Have you put a 30 amp load on a cell to see what it does for voltage? How fast can you charge them? The 2s3p pack I use is good for 90 amps continuous and 10 second bursts of 170 amps. I can recharge in 15 minutes or less and with a 40 amp load applied they hold 2.8-2.9 volts per cell. These are the 1100mah (18650) cells, the 2300mah cells(26650) will do a continuous 70 amps with 10 second bursts of 120 amps in a 1p format....BB
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Old 12-17-2008, 05:16 PM   #663
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They seem to fit well, I see they are 30c and if I do the math I come up with 28.5 amps then in a 2p format I get 57 amps. That seems marginal at best, do they feel like they hold there voltage under a load? Have you put a 30 amp load on a cell to see what it does for voltage? How fast can you charge them? The 2s3p pack I use is good for 90 amps continuous and 10 second bursts of 170 amps. I can recharg in 15 minutes or less and with a 40 amp load applied they hold 2.8-2.9 volts per cell. These are the 1100mah (18650) cells, the 2300mah cells(26650) will do a continuous 70 amps with 10 second bursts of 120 amps in a 1p format....BB
I have'nt done any bench testing, just track testing and only with a 17.5. But with the 17.5 I had excelent acceleration and good rip untill these cells dump. This was on a med size carpet track, and no I did'nt time the recharge cycle so I canot say on that.

Do you have a link to the cells you've been using? I'd be interested in looking/trying them myself.
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Old 12-17-2008, 05:27 PM   #664
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Look - 3.7v LiPo is not sensible since it will require the use of a Receiver Pack. That means that another battery on our cars, and another battery that will need to be ROAR approved, thus raising the cost again. Most people are turning to 1/12 racing from Sedan racing as a way to race at reduced cost, but now we are wanting to increase the cost again.

This is so simple, it is slapping us around. Keep NiMh for now, then transition to a 7.4v LiPo. If this is too fast for the "Stock" crowd, drop down to a 21.5 motor, as gearing will be very close to a 17.5 motor running 4-cell NiMh.
ROAR dropped 7.2V from 1:12 several years ago, do you think they will bump up to 7.4V LiPO that has 30C discharge rates? Come On 2000mah NiMH with 20A discharge gave the cars too much speed and putting a 21.5 in the car will not solve every thing.

I did not know ROAR had rules for the RX batteries used, so please share what you know.
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Old 12-17-2008, 05:31 PM   #665
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Any change that doesn't let me go back to NiMh for big races is not a good option as far as I'm concerned. That means no major changes to the car like new pod or main chassis.
Run 3-cell NiMH at the big races with the 3.7V LiPO's. No biggie on new chassis, there is enough stuff that can be moved around to blance a car.
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Old 12-17-2008, 05:42 PM   #666
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...I did not know ROAR had rules for the RX batteries used, so please share what you know.
They don't YET...but with all the posibilities to back feed you bet they will, also will have to temp batteries and Voltage test, just like they have to for touring to prevent guys from performing unsafe practices for every advantage.
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Old 12-17-2008, 08:05 PM   #667
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I'm still trying to figure out what everyone has against brushed motors? Skim the comm once a week and change the brushes maybe once every 8 race days at most. More infield punch and car setup is not near as critical. To be fast in brushless you have to have your car perfect so it does not slow down at all in the corners and if for any reason you have to let off the gas for traffic you lose a lot of ground. Yes, they don't fall off at the end of 8 min like a brushed motor, but I see no advantage on the track other than that. The only advantage is that you can leave the motor in the car for the whole season if you want. For me, working on the motors is part of the fun of racing.

I have not tried Lipo yet but it does appeal to me in that you only need one battery and can leave it there for a month if you want. And you don't have the "who's got the biggest voltage and run time thing", but I'm waiting for all of the manufacturers to get to a point where there won't be a battery of the week. Times are tough all over, and racers should be able to spend their hard earned money on comsumable stuff like tires, bodies, broken parts and entry fees, not a new LIpo pack every couple of weeks.

I never saw 1/12 scale as being broken, so why does it need to be fixed? I'm all for technology advancement, but not at the cost of running people off. Anyone try running lipo with a brushed motor? That sounds interesting to me.7.4v with a stock 27t was a lot of fun back in the day.

I will go put my flame suit on now.
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Old 12-17-2008, 08:51 PM   #668
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I'm still trying to figure out what everyone has against brushed motors? Skim the comm once a week and change the brushes maybe once every 8 race days at most. More infield punch and car setup is not near as critical. To be fast in brushless you have to have your car perfect so it does not slow down at all in the corners and if for any reason you have to let off the gas for traffic you lose a lot of ground. Yes, they don't fall off at the end of 8 min like a brushed motor, but I see no advantage on the track other than that. The only advantage is that you can leave the motor in the car for the whole season if you want. For me, working on the motors is part of the fun of racing.

I have not tried Lipo yet but it does appeal to me in that you only need one battery and can leave it there for a month if you want. And you don't have the "who's got the biggest voltage and run time thing", but I'm waiting for all of the manufacturers to get to a point where there won't be a battery of the week. Times are tough all over, and racers should be able to spend their hard earned money on comsumable stuff like tires, bodies, broken parts and entry fees, not a new LIpo pack every couple of weeks.

I never saw 1/12 scale as being broken, so why does it need to be fixed? I'm all for technology advancement, but not at the cost of running people off. Anyone try running lipo with a brushed motor? That sounds interesting to me.7.4v with a stock 27t was a lot of fun back in the day.

I will go put my flame suit on now.

Really its allways been my opinion/understanding that brushless has much more bottom end thus the higher rollout needed over brushed. Not flameing just tring to understand your statment that brushless has less grunt in the infield.

Really I think that many posters that have expressed negitave comments or comments like leave 1/12 alone its not broken misunderstand the purpose of this thread. Sure changes will very likely happen in 1/12 but this thread is'nt about forcing a change to 1/12. Rather that some of us like to tinker; push the envelope so to speak and look at other alternitives and ways to do things. I have no problem staying with 4-cell nimh, but it would be nice to have a lipo or other battery alternitive avalible. Now as to why I like brushless over brushed; well I never was all that good at tunning a brushed motor and would much rather spend that time driving instead of wrencing in the pits. And if you do have an advantage in the twisties I'll just wave as I pass you on the backstraight with my brushless
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Old 12-17-2008, 09:07 PM   #669
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Skim the comm once a week and change the brushes maybe once every 8 race days at most
Comm lathes aren't exactly cheap
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Old 12-17-2008, 09:33 PM   #670
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Really its allways been my opinion/understanding that brushless has much more bottom end thus the higher rollout needed over brushed. Not flameing just tring to understand your statment that brushless has less grunt in the infield.

Really I think that many posters that have expressed negitave comments or comments like leave 1/12 alone its not broken misunderstand the purpose of this thread. Sure changes will very likely happen in 1/12 but this thread is'nt about forcing a change to 1/12. Rather that some of us like to tinker; push the envelope so to speak and look at other alternitives and ways to do things. I have no problem staying with 4-cell nimh, but it would be nice to have a lipo or other battery alternitive avalible. Now as to why I like brushless over brushed; well I never was all that good at tunning a brushed motor and would much rather spend that time driving instead of wrencing in the pits. And if you do have an advantage in the twisties I'll just wave as I pass you on the backstraight with my brushless
The basis for my findings is from racing with Sean Cochran and Jimmy Peirsol this past weekend and I would consider both of them very knowledgeable. Both said that they felt like it took a long time for their brushless motors, both 17.5 & 13.5, to get back up to speed after having to let off. Sean also mentioned that you almost needed to have your car set up to be able to get around the track without lifting at a big race, at least fully lifting, as you lose too much time. I ran a 5 year old brushed handout motor and was easily faster in the infeild, but yes, they were both faster on the straight. In all lap time were about the same. Jimmy was running 3.7v lipo/13.5 and Sean was running Nimh/17.5.

I'm not saying that it's a bad thing to come out with new technology, just that manufacturers should try to keep it affordable to keep racers around and to get new ones in. There will always be those that what to spend whatever it costs to have the latest and greatest and that needs to happen when new products are being deleveloped. Just don't change the class to where an average guy gets run out because he has older equipment. For someone like me that's been in the hobby for a very long time, the cost to switch over to lipo and brushless is huge and could run some racers off. Not everyone has an extra $500 laying around to buy a new esc/motor combo, lipo packs and the chargers/balancers, etc. that are needed.

I guess I did miss the purpose of this thread and apologize for steering it off track. I for one look forward to the day when we have solar powered hovering cars that you no longer have to true tires for. I hate trueing tires!

Now back to your previously scheduled program................
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Old 12-17-2008, 09:47 PM   #671
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Originally Posted by kn7671 View Post
Look - 3.7v LiPo is not sensible since it will require the use of a Receiver Pack. That means that another battery on our cars, and another battery that will need to be ROAR approved, thus raising the cost again. Most people are turning to 1/12 racing from Sedan racing as a way to race at reduced cost, but now we are wanting to increase the cost again.

This is so simple, it is slapping us around. Keep NiMh for now, then transition to a 7.4v LiPo. If this is too fast for the "Stock" crowd, drop down to a 21.5 motor, as gearing will be very close to a 17.5 motor running 4-cell NiMh.
I had no idea they had crack in Texas...
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Old 12-17-2008, 10:08 PM   #672
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I have'nt done any bench testing, just track testing and only with a 17.5. But with the 17.5 I had excelent acceleration and good rip untill these cells dump. This was on a med size carpet track, and no I did'nt time the recharge cycle so I canot say on that.

Do you have a link to the cells you've been using? I'd be interested in looking/trying them myself.
I use the 18650 cell in a 2s3p config, there is info here under products.
http://www.a123systems.com/

I have a bunch of cells and I bought mine at my local hardware store,home depot and wal-mart. This is what they look like and you could get them here, each pack has 2 cells so you would need 3. I posted a few pictures a ways back in the thread but I can post some new one's if you like.....BB

http://www.amazon.com/Black-Decker-V.../dp/B000UME3JC

Or here but a little more money
http://www.acehardware.com/product/i...ductId=2889011
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Old 12-17-2008, 11:18 PM   #673
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They are now...
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Old 12-18-2008, 03:00 AM   #674
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Look - 3.7v LiPo is not sensible since it will require the use of a Receiver Pack. That means that another battery on our cars, and another battery that will need to be ROAR approved, thus raising the cost again. Most people are turning to 1/12 racing from Sedan racing as a way to race at reduced cost, but now we are wanting to increase the cost again.

This is so simple, it is slapping us around. Keep NiMh for now, then transition to a 7.4v LiPo. If this is too fast for the "Stock" crowd, drop down to a 21.5 motor, as gearing will be very close to a 17.5 motor running 4-cell NiMh.
That's not looking to the future, that's accepting the past. It is unlikely that 7.4v will be accepted, because it makes the cars too fast for both beginners, and safety - been there, seen that, change it to 4.8v. In the future, someone will develop a voltage doubler that runs the car from the 3.7v pack (they are already available, and have been used, but may need more output. Novak has one now I believe) and then the extra battery is not required. If you are looking to the future, keep looking that way, and not backwards to find some scrap of data that supports your view.

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I am just curious to see what everyone’s opinion is on the speed of the current STOCK class? Why should we try to "match" what speeds we currently run in Stock just to make a battery change/substitute "acceptable"?

In my opinion I would rather the cars slow down a lot; a lot of people (mainly beginners) now can't handle the stock speeds and as fast as the cars there needs to be 2 separate divisions like nitro races (pro and amateur) in stock just to keep the fast and slow guys happy.

How about we let modified be 'run what you brung' and stock being an entry level class. This lets everyone run what equipment they have and what is ROAR legal, plus now the drivers w/ a high level of talent can finally step up to Mod where there would be a full heat of 10+ instead of just 2 or 3.

What do you guys think?
I think you are spot on. I don't think people realise how fast the cars have become through chassis and tyre developments in the last few years. We use 10.5 as our Stock class, and today they are as fast as an old 12 double BR. Yet, most of our racers now choose 10.5BL where in the past they would not have chosen a 12T BR.

Elsewhere on this forum, people are talking about cars with 13.5 in (faster than 27T BR) able to be driven flat out everywhere, when this wasn't possible even three years ago.

If the class is to remain cheap and accessible, then it needs to remain as easy as possible. 3.7v with a 13.5BL and a voltage doubler would be easy for everyone, to both get in the shops, and to drive. Same for us - within a couple of years, a 10.5BL powered by 3.7v LiPo will be giving the same lap times as today's 4.8v cars.

Leave the Rules as they are (4.8v max) so that as LiPo dies off to be replaced by A123 and the Panasonic 2.4v cell, we can continue to take advantage of what the future holds, and not change our Rules so that we cannot take advantage of the future.

The future of 12th scale is to leave the Rules as they are, and find the technologies we need to make the new developments work. This is what TC and Off-Road have done over here, and it works.

I notice that there are more and more posts from people running 3.7v LiPo who are liking it, and making it work. Some are even finding their lap times faster because the car is easier to driver. Things develop faster under a stable regime of Rules, so let's get on with it under the Rules we have.
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Old 12-18-2008, 03:55 AM   #675
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I had no idea they had crack in Texas...


Seriously though, we've seen touring car take a huge dive, most of which had to do with cost. I just don't want to see any changes made without first considering the longterm impact of the classes health and survivability.

If the majority and ROAR come to agree that 13.5 and 3.7v LiPo is the new way to go, and rules are made to support it, than I will race what the rules say.

Last edited by kn7671; 12-18-2008 at 06:27 AM.
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