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Old 01-09-2008, 02:44 PM   #31
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Originally Posted by Ed237 View Post
Yeah, your right, Cavalieri, Tebo, Maifield have no idea what they are doing!

Sorry to use the sarcasm, but, to put it in perspective, AE designed the T4 to be heavier than ROAR rules and their drivers are adding weight to it. The people who design and race the cars for a living are advising you to add a few grams to your car to make it easier to drive.

I don't know why. Maybe motors and batteries have improved over the last 10 years to the point where they have exceeded a reasonable power to weight ratio that makes driving them too unpredictable unless they have some strategically placed ballast.
I am really just disagreeing with your last statement about recommendations to add weight disproves that a light car is faster. In fact you yourself just referred to strategically placed ballast. That's mostly what the addition of weight is for...not to simply make the car heavier. That's why the top drivers add [very little] weight. It's a complicated equation we are hashing out here!!

Lighter?
Better Balanced?
More weight on the tires?

I don't think we'll really come to a reasonable conclusion which we all agree upon.

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Old 01-09-2008, 03:18 PM   #32
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Rather than keep debating hypothetically which one would be faster, is it possible to try this concept out on the track? The 380 can and the 540 can have different mounting holes, so first, you'll need a 380 to 540 adapter or a different motor plate on 1/10 scale buggies and trucks. Next, is the 380 shaft long enough to support a pinion if you use a 380 to 540 adapter? Then, how can you get 48p pinions for 540 motors to fit a 380 motor. I believe the 380 motor shaft is smaller than a 540 motor shaft. The other option is to use larger pinions for the 380 motor, but I've only seen 15t to 20t pinions for the RC18T. It would be nice to get sizes 21t to 27t for some lower RPM motors.
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Old 01-09-2008, 03:41 PM   #33
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A smaller motor will typicaly rev higher thus a low turn pinion will still work great.
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Old 01-09-2008, 03:46 PM   #34
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Originally Posted by edlan View Post
Rather than keep debating hypothetically which one would be faster, is it possible to try this concept out on the track? The 380 can and the 540 can have different mounting holes, so first, you'll need a 380 to 540 adapter or a different motor plate on 1/10 scale buggies and trucks. Next, is the 380 shaft long enough to support a pinion if you use a 380 to 540 adapter? Then, how can you get 48p pinions for 540 motors to fit a 380 motor. I believe the 380 motor shaft is smaller than a 540 motor shaft. The other option is to use larger pinions for the 380 motor, but I've only seen 15t to 20t pinions for the RC18T. It would be nice to get sizes 21t to 27t for some lower RPM motors.
Half this site is hypothetical debating...if we stopped doing that, what else would we talk about?
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Old 01-09-2008, 03:50 PM   #35
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I was also looking at the power output of the typical mod 380 motor.

With 3 cell lipo, 11.1v, they are pulling about 12 amps, which means these motors are putting out 130 watts, which is about the typical output of a 540 size 27t stock motor with 7.2v.

http://www.castlecreations.com/products/cm-2054.html

So it seems the 380 size motor can put enough power to run a 1/10 scale, but just barely. A mod motor for 1/10 scale, like a Novak 6.5 will put out 390 watts.

http://www.teamnovak.com/products/br...spec_chart.htm

Also, you still need a 380 to 540 adapter which I haven't seen for sale.
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Old 01-09-2008, 03:58 PM   #36
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Actually, I have a racing buddy that did use a 380 motor with a 3s lipo setup in his 2wd car . He swiss cheesed the thing and even cut the sides off the chassis and wound his own springs. It wasn't faster because at 1.75lbs. there really was not enough weight to get traction (he even tried cut down rear rims with front 4wd tires on them). He still runs his 4wd with the 380 in runner and 3s lipo about 1/2lb below legal weight and it works pretty well.
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Old 01-09-2008, 04:07 PM   #37
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You can find 380 sized motors that will draw around 25 amps which will give you around 200 watts on a 2s lipo. As far as traction is concerned you really need to have some experience w/ setups b4 you can conclude that the car will not have good traction.
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Old 01-10-2008, 12:17 AM   #38
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like in real racing everything is a balance, to much of one thing, and not enough of another doest make it better. Also track condition plays into the whole thing, as well as the little bit of down force produced helps with traction. In first page people were talking about making cars STRONGER, and as a result they would be heavier. The point is that current 2 and 4wd 10th scale can always have more power put in them with current motors and batteries, therefore the performance would not be limited as much, although their would be some consequences to change in direction and things like that, but as it was said before, the right setup and balance needs to be found for any situation.
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Old 01-10-2008, 05:21 AM   #39
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Ah the memories, these pictures are from over two years ago.


My current 3S-3600mAh 380BL power car pulls 500 watt spikes and 350 watt continuous. That's with the low kv motor, it is more like 750 watts with the 4400kv motor (Himax 2825-4400)! Dave can attest to that.
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1000 gram 2wd-960grams.jpg   1000 gram 2wd-b4_nothin_left.jpg  
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Old 01-10-2008, 06:02 AM   #40
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Totally agree with party_wagon on this. My friend and I have often thought that 540-sized brushless motors are totally unnecessary. They have the potential to overpower cars in both on and offroad, so all we are really doing is carrying unnecessary weight. Durability is suffering - eg some cars are breaking more belts as a result. Some are running 5 cells in touring to make the cars more driveable and are starting to dump with 4000+ mah cells! Meanwhile manufacturers continue to cram more capacity into the confines of already volatile Sub-C cells but that is another thread altogether...

Bringing down the minimum weight limits will make our cars more efficient and more durable. Once you adjust your setups to suit, the cars will handle even better because the smaller motors will substantially lower your centre of gravity.
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Old 01-10-2008, 06:20 AM   #41
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Ah the memories, these pictures are from over two years ago.


My current 3S-3600mAh 380BL power car pulls 500 watt spikes and 350 watt continuous. That's with the low kv motor, it is more like 750 watts with the 4400kv motor (Himax 2825-4400)! Dave can attest to that.
What did you end up using for a motor mount?
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Old 01-10-2008, 07:54 AM   #42
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Originally Posted by RC8 View Post
Ah the memories, these pictures are from over two years ago.


My current 3S-3600mAh 380BL power car pulls 500 watt spikes and 350 watt continuous. That's with the low kv motor, it is more like 750 watts with the 4400kv motor (Himax 2825-4400)! Dave can attest to that.
That is sweet. How does it run? I noticed you put what looks like 4WD fronts on the rear for the weight pic. Did you get those to mount up to run it with them, or was is just for the < 1000g photo op? I'll have to see if I can find your old thread on it cause I want to hear more about this project.
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Old 01-10-2008, 10:09 AM   #43
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I'm not sure if this is small enough, but it shouldn't be too hard to make a motor mount for this. fits 16 or 19mm bolt pattern to a 540 pattern.

http://holmeshobbies.com/product.php...&cat=19&page=1
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Old 01-10-2008, 07:30 PM   #44
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i dont see the point in introducing another standard into r/c. we want to keep as little as possible. your motor too powerful? run stock or adjust your esc if you can like mamba max or turn down your exponential curve. if you dont have an exponential curve you shouldnt be worrying about too fast of a motor you need a better radio first. and the best thing if all you can control the throttle with your finger to give you less wheel spin. its one part of being a good racer its not all about steering if about throttle control too.

if you want to break your car less then learn to drive maybe start with a slower motor if your not competitive in mod then race stock class, if you dont have stock class then deal with it as mentioned in the other thread we cant all be winners. i broke both my cars once all summer and no im not a top 3 amain driver but thats ok because im racing for fun and yes i do want to someday win the a main but i dont want to do it by complaining that the cars are too fast or the cars are too hard to drive and have the rules or classes changed to suit me. if you want to run a smaller motor then do it just dont try to make another class out of it. r/c cars are gonna become slot cars soon next thing you know we have assisted steering, ABS and traction control.

8th scale cars dont break as often mostly because they are mostly aluminum or stuff like arms are 10mm thats over twice the thickness of 10th scale cars and they are very wide.

the best real car rally class, group b, was canceled because the cars were too fast and light lets not have that in r/c.
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Old 01-10-2008, 08:05 PM   #45
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That is sweet. How does it run? I noticed you put what looks like 4WD fronts on the rear for the weight pic. Did you get those to mount up to run it with them, or was is just for the < 1000g photo op? I'll have to see if I can find your old thread on it cause I want to hear more about this project.
I never got it to run very well. I think I didn't have the right tire combo to get grip on our track, normally slick pinks. I did run it just as it weighs in. I had a very small motor in it for that. Probably a 2820 ish motor. That motor eventually fell apart, the internal rotor magnets came off the rotor.

I mounted all of the small motors right to the B4 motor plate. I used one existing hole and the other bolt came through the hole for the motor shaft. Kind of ghetto but it worked.

Not much detail in the other thread, but here are a few more pictures of when I got REALLY bored. Obviously I got bored with the drill and eventually went for the hack saw.
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1000 gram 2wd-drilled_chassis_chips.jpg   1000 gram 2wd-drilled_chassis.jpg  
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