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Old 12-04-2009, 11:23 PM   #46
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Originally Posted by WheelNut View Post
Onto rant #3:
How to make touring car better for new guys.
Make the IFMAR WC A mains really long. That way the manufactures will be required to make their cars really, really strong to survive. The only reason 1/8th buggies are so strong is because of 1 hour mains. The cars have to survive to be competitive. This has the side benefit of making the car inherently beginner friendly. Minimum weights will never make cars stronger because it's faster to add lead to a car than to make belts wider, or add gear diffs, or thicken suspension arms.
1. 30 minute mains at all IFMAR WCs. Hard barriers necessary (N.A. style).
2. Gear diffs mandated standard.
3. Minimum 6mm wide belts.

My slightly odd $0.02
I like the theory, but..

That will make touring that much more expensive. Kits, Parts..
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Old 12-04-2009, 11:31 PM   #47
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Lots of good banter in here, I appreciate the thoughtful replies.

As far as capacity is concerned, we have the ability to rule that out as a factor by keeping packs the same size. Existing 5200 packs could be re-wired into 10400 and probably make capacity a moot point.
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Old 12-05-2009, 12:26 AM   #48
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Only if you don't set the lipo cutoff correctly. People run 1/8th electric offroad buggies down to lipo cutoff all the time with no adverse effects on the batteries. And those cars draw WAY more power out of the cells than any mod TC could ever hope too.
As someone whose tried to make more than a couple 20 min mains with my 4s 6000 mah in my 8ight buggy, I can attest to the beating a battery takes if you routinely discharge them too far. they certainly loose their punch.

As for the 1s idea I really like!
It will really make the hobby accessible by bringing down the costs and speeds

I think its important to recognize that we are actually trying to solve two completely separate issues with one change.

Issue 1;
Mod cars are too fast. The word "open" has an entirely new meaning with 2s and brushless. running 1s would certainly solve this problem - barring the whole increased current/temp/resistance issue that im not gonna try to act like i know anything about.

Issue 2;
17.5, and 13.5 are too fast (relatively). I think even with the black magic speedo of the week, 17.5 is still slow enough for newbies. The problem is that the relative speed of the guy with the best equipment is way faster than the poor new guy trying to make his GTB work. This can make racing frustrating and unaccessible - Even for someone like me who knows what the best stuff is (I feel like I have to get a new esc every 6 months to keep up). This isnt new though - Guys were making stock racing just as frustrating by tweaking 27 t motors a few years back

I really doubt that 1s would solve this - the newest greatest speed control is still gonna make the pro way faster than the new guy no matter what voltage you run.
I think to solve this there needs to be stricter regulation on speed controls. Sure all the new profiles and settings may look like black magic to us, but the engineers at LRP, Speed Passion, and KO know exactly what they are doing. If there was somebody who was savvy to all this at ROAR who could mandate power consumption for escs and make a roar approved stock esc with roar approved timing and profiles i think alot of the problems would be solved

my $.02
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Old 12-05-2009, 10:27 AM   #49
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"In a three phase system, power P = U * I * sqrt(3) * cos(phi), where U is the voltage (rms), I the amperage (rms), sqrt(3) is the square root of three, and cos(phi) is cosine of phi, where phi is the angle between U and I. For pure resistive load, phi is zero (i.e. cos(phi) = 1), making the calculation pretty easy in this case. For inductive or capacitive loads such as motors or flourescent lights, phi moves to different values and must be estimated, measured, or calculated.

Find the Amperage of an 7200w inductive (i.e. motors, pumps, fluorescents etc.) load on a 415 Volt,
3 phase

branch circuit.

I = 7200 / (415 x 1.732) = 10.01 Amps per phase."

solve for 240V

I = 7200 / (240 x 1.732) = 17.32 amps per phase


-From wiki answers


Lower voltage creates higher amp draw
ps you have 3 phase to the motor
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Old 12-05-2009, 10:40 AM   #50
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I am not missing any point. You need to go back and re-read what I was saying. Yes a 3.5 turn motor has less resistance because there is less wire than a 13.5.
Fewer turns already reduces the internal resistance not KV. KV is a measurement.

I was pointing out to David that you can not create amperage as he implied.
You've missunderstood what I implied. I am implying that if a change to 1s occurs it will almost definitely be accompanied with a motor change, I do not believe that the 13.5 class would continue to run 13.5's on half the voltage so the amp draw does increase when the motor's power changes to offset the voltage drop.

The only answer to all this I can see is to technically limit the spec classes to keep them that way. This means removal of timing advance speed controls from one or both the current spec TC classes. TC's health has been greatly improved with the advent of lipo and brushelss, it was briefly so much less of a wallet race. As it is now, 13.5 is the mod class and mod racing seems almost non-existent. This makes 13.5 take the place that mod once occupied (the expert's class). I would propose that timing advance be pulled from 17.5 to reduce the cost of entry for new racers and to keep costs down for experienced racers that want a spec class.
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Old 12-05-2009, 10:58 AM   #51
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Spec racing like 17.5 is a whole different scenario, and might need to be left out of the discussion for the time being since there's so many other hurdles on the horizon.

I was thinking more about trying to revive interest in the mod class, and to possibly find a way to unify the 13.5 crowd with the mod crowd since there seems to be a lot of interest in only going with two classes, and we're starting to spread ourselves thin.

The general impression I get from the pros is that they wouldn't mind slowing down mod, but they don't want to make it spec motor. Does 1S potentially solve that? Or would we start to see 1.5T motors and melted batteries?
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Old 12-05-2009, 11:20 AM   #52
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Originally Posted by syndr0me View Post
The general impression I get from the pros is that they wouldn't mind slowing down mod, but they don't want to make it spec motor. Does 1S potentially solve that? Or would we start to see 1.5T motors and melted batteries?
I think it could go either way

Look at the last euro touring race that was on red rc. Mark and all those guys ran 4.5's on lipo. You cut the voltage in half you cut the rpm in half, so obviously with 1s your going to have to motor up to get some sort of speed back. But even a 4.5 on 1s lipo will turn around 10,000 more rpm (roughly) more then a 13.5 on 2s. So it would still be faster then super stock. And I guess if you could run 1s and lower the min weight (ohh jeeze) that would help out also?
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Old 12-05-2009, 12:23 PM   #53
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why slow anybody down, if you can`t handle mod don`t run in it.
These ideas are only going to increase cost because now you need the find faster motors, speed controls and another battery wars.
after you slow everybody down and still can`t beat the pros whats next? quit counting laps so no loosers?
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Old 12-05-2009, 12:31 PM   #54
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Originally Posted by robk View Post
Electrical systems run more efficiently at higher voltage.
..........yup.......
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Old 12-05-2009, 01:16 PM   #55
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Originally Posted by BlackedOutREVO View Post
I think it could go either way

Look at the last euro touring race that was on red rc. Mark and all those guys ran 4.5's on lipo. You cut the voltage in half you cut the rpm in half, so obviously with 1s your going to have to motor up to get some sort of speed back. But even a 4.5 on 1s lipo will turn around 10,000 more rpm (roughly) more then a 13.5 on 2s. So it would still be faster then super stock. And I guess if you could run 1s and lower the min weight (ohh jeeze) that would help out also?
yes, the guys running 1s mod are NOT at the current minimum weight. they only use enough added weight to balance the car side to side.
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Old 12-05-2009, 01:20 PM   #56
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Quote:
Originally Posted by robk View Post
"In a three phase system, power P = U * I * sqrt(3) * cos(phi), where U is the voltage (rms), I the amperage (rms), sqrt(3) is the square root of three, and cos(phi) is cosine of phi, where phi is the angle between U and I. For pure resistive load, phi is zero (i.e. cos(phi) = 1), making the calculation pretty easy in this case. For inductive or capacitive loads such as motors or flourescent lights, phi moves to different values and must be estimated, measured, or calculated.

Find the Amperage of an 7200w inductive (i.e. motors, pumps, fluorescents etc.) load on a 415 Volt,
3 phase

branch circuit.

I = 7200 / (415 x 1.732) = 10.01 Amps per phase."

solve for 240V

I = 7200 / (240 x 1.732) = 17.32 amps per phase


-From wiki answers


Lower voltage creates higher amp draw
ps you have 3 phase to the motor
My wifes vibrator slows down when the battteries start to die, not sure if it heats up though.
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Old 12-05-2009, 01:37 PM   #57
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Donīt mind the proīs, they can adapt to any rules and be on top. I think slower cars could attract more people to try touring cars and why not test 1s lipo. Maybe as a support class to try things out.

I remebered when we switched to five cells here in Europe and initially it worked great; slower cars, less strain on the drivetrain, lighter cars. But soon the batteries (sub-c) started to get better and better so people started to put in motors with less winds. Now with lipo and 1350g cars are really fast (too fast?) but lipo have level the playing field. No need for special team batteries anymore.

So a 6V lipo would be perfect.
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Old 12-05-2009, 03:03 PM   #58
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Lots of good ideas here, but I don't understand how slowing down open mod is going to fill races.
Here is my 2c.

1. Mod is mod--where the fastest and best drivers figure out (between set up and driving skill) how to strap in and lay down more and more power.
Why should the elite class be handicapped to become more accesible to the masses?

2. If a slower class is needed, it seems we already have those (21.5, 17.5, 13.5)--and yet here we are discussing a shrinking TC class.

3. I think the solution to shinking turnouts lies in rekindling the BASICS of what make TC Racing cool in the first place--things like scale realism, the ability to race in a parking lot, adjustability, and killer speed/acceleration.
Glimmers of hope like WGT, F1, (and the Slash class in offroad), point to this fact.
Rules are rules, but like fences, rules can only manage the substance of what is already there.
For TC to flurish, we need a substantive change, not a topical re-arrangement of the same old, same old.

4. What might this mean?
*Well how about cheaper, simpler, more durable cars?
I've raced since TC started in the mid 90's, and while the cost (of time and money) to competitive has easily doubled, my enjoyment has not. It is much harder for me to field a winning car now (again in terms of time and money) than ever before. Is the excitement on the track somehow better, or more intense knowing you spent two to three times more than you used to?
*How about cheaper, longer life tires? A little less grip will balance out the field. Longer life and less cost, less frequent will bring more people in than a slower mod class (to say nothing about helping out those that run mod!)
*How about a greater choice of more realisic, less aero-serious bodies?
I know watching my Tamiya Alfa 155 cruise around the track atop my TA01 was a cool experience--one that I have yet to best, and will never forget.

--Brett Sisley
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Old 12-05-2009, 03:07 PM   #59
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Originally Posted by DIALED View Post
Lots of good ideas here, but I don't understand the idea of slowing down open mod.

1. Mod is mod--where the fastest and best drivers figure out (between set up and driving skill) how to strap in and lay down more and more power.
Whey should the elite class be handicapped to become more accesible to the masses?

2. If a slower class is needed, it seems we already have those (21.5, 17.5, 13.5)--and yet here we are discussing a shrinking class.

3. I think the solution to shinking turnouts lies in rekindling the BASICS of what make TC Racing cool in the first place--things like scale realism, the ability to race in a parking lot, adjustability, and killer speed/acceleration.
Glimmers hope like WGT, F1, (and the Slash class in offroad), point this fact.
Rules are rules, but like fences, rules can only manage the substance of what is already there.
For TC to flurish, we need a substantive change, not a topical re-arrangement of the same old, same old.

4. What might this mean?
*Well how about cheaper, simpler cars? I've raced since TC started in the mid 90's, and while the cost (of time and money) to competitive has easily doubled, my enjoyment has not. It is much harder for me to field a winner car now (again in terms of time and money) than ever before. Is the excitement on the track somehow better, or more intense knowing you spent two to three times more than you used to?
*How about cheaper, longer life tires? A little less grip will balance out the field. Longer life and less cost, less frequent will bring more people in than a slower mod class (to say nothing about helping out those that run mod!)
*How about a greater choice of more realisic, less aero-serious bodies?
I know watching my Tamiya Alfa 155 cruies around the track atop my TA01 was a cool experience--one that I have yet to best, and will never forget.

--Brett Sisley
Amen!
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Old 12-05-2009, 03:56 PM   #60
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If you are looking to rekindle the interest in sedan I tend to agree with the thoughts on the cars/kits are the area that needs to be targeted. I know in my area that the class thrived when the TC3, G+ type cars were what we raced. The $199 kits ruled the day. Also the cars were much more simple and less parts or hop ups were needed. If you look at the landscape of electric racing you see that off road chugs along at that price break. Here people had the choice between on or off road and that was a coin flip money/setup/breakage wise. Now we see the cost of off road still in that same range and the car kits more then doubled in price, much more advanced and always changing. A $400 fragile car just is not going to bring in the new racer or keep the old on road guy on a budget.
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