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I want to go faster!! (TC4 & Mamba 5700K)

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Old 03-26-2009, 12:51 PM
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TomTomTuning
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Default I want to go faster!! (TC4 & Mamba 5700K)

Team Kit TC4
Mamba 5700K
3S 4000Mah Lipo
20T Titanium Pinion
72T stock Spur
Current FDR: 9.00

CC "recommends" a Pinion of 13-18T and the largest spur i can get.

If i go to a 18/75 that will make my FDR 10.42
But wouldn't that hurt my top-end?

Higher FDR = More acceleration (less top end)
Lower FDR = More Top end (less acceleration)

If i want more speed, should i just switch to a 4S Lipo?
(i know i voids my warranty, and i have to disable the bec and run something like a CCBEC. Maybe even add a Power Cap & Fan if need be)

Or should i optimize what i have and tweak the gearing some. (any recommendations)

I'm looking for about 65-75MPH range. (No clue what I'm currently at)
Opinions are much appreciated. Thanks!
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Old 03-26-2009, 03:52 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

This is funny... I just came back from running my car and i too was looking for more speed. i also have the TC4 factory team

originally, i was running the mamba 5700 with a 2s 5400 lipo with 72/20 gearing and the car was fast.
I then put in the mamba 7700 motor with the same setup and the car was #*#*ing fast

Last night, i installed an 81 tooth Spur( which is the largest that will fit, and still needs a little dremmel work)
and an 18 pinion.. with a 3s 4000 lipo and back to the 5700 motor as instructed by Castle.

I find the car slower..yet they state this should be the fastest setup.

So i am in the same boat...although I have never figured How to analyze the gearing ratios.

What is the math equasion??
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Old 03-26-2009, 05:49 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

ORIGINAL: TomTomTuning
If i go to a 18/75 that will make my FDR 10.42
But wouldn't that hurt my top-end?

Higher FDR = More acceleration (less top end)
Lower FDR = More Top end (less acceleration)

If i want more speed, should i just switch to a 4S Lipo?
(i know i voids my warranty, and i have to disable the bec and run something like a CCBEC. Maybe even add a Power Cap & Fan if need be)

I'm looking for about 65-75MPH range. (No clue what I'm currently at)
I was running a very similar setup in my TC4 once. 5700 motor, 3s LiPo. The LiPo was a maxamps 3s 4000mAH (this was 2+ years ago).
http://www.youtube.com/view_play_lis...9143C64687ABE9
I started out at 19/78 and eventually moved up one or two teeth at a time to 25/75. By the end I had a powerful 8 watt, 14000RPM 40mm fan blowing air to keep the ESC and motor cool. With 25/75 I could hit a reliable 65mph, confirmed with a radar gun. 19/78 it would top out around 54mph.

I ignored the Higher/Lower FDR thing. I found it was absolutely useless in practice. The car had monster acceleration no matter how I geared it. I prefered the 19/78 gearing b'cos with 10 'punch control' I could floor the throttle from a dead stop and not lose traction. When geared higher, the punch control simply didn't have the range to let it accelerate without losing traction if I floored it.

If you have a batter that can provide enough current, your only concern when gearing is the temperature of the motor and ESC. If they are not too hot, keep increasing it to your hearts content. I don't know when you'll start to noticeably limit your acceleration but I was running 25/75 and my acceleration was basically beyond what the tires could handle.

There is no reason to run 4s LiPo with a 5700 motor. Unless you are drag racing. The bearings are made for ~65000RPM. Their newer motors might be able to handle 80,000RPM or so, due to better bearings, but those are just things you hear.
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Old 03-26-2009, 06:40 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

To add.....I just came across this link ... awesome tool and all guesswork is gone. http://dhrc.rchomepage.com/RolloutCalc.htm


If I enter my exact setup as shown on my first post. With a 100% charge I only generate 50.1 MPH.

In fact the above statement bythe other poster is correct, you need to a setup like 75/22to reach 60 MPH and then go up from there, but yo uneed big time cooling.

What i dont like, it that according to the chart on Castle creations site, when you run the 3 s lipo and the 5700 motor, they tell you to install the largest spur you can fit and then up to an 18 tooth pinion...which is what I did.

I just emailed them since this seems to be inaccurate info, seeing that i did this exactly and get at most 45 mph

My 2s lipo 5400MAh with the 7700KV motorand a 72/20 was siginificntly faster.
Interestingly, and as shown on the same chart at castle, this setup is good for over 50 so their chart is accurate since the entered setup on the link would generate 53.5
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Old 03-27-2009, 06:24 AM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

ORIGINAL: fergup1

This is funny... I just came back from running my car and i too was looking for more speed. i also have the TC4 factory team

originally, i was running the mamba 5700 with a 2s 5400 lipo with 72/20 gearing and the car was fast.
I then put in the mamba 7700 motor with the same setup and the car was #*#*ing fast

Last night, i installed an 81 tooth Spur( which is the largest that will fit, and still needs a little dremmel work)
and an 18 pinion.. with a 3s 4000 lipo and back to the 5700 motor as instructed by Castle.

I find the car slower..yet they state this should be the fastest setup.

So i am in the same boat...although I have never figured How to analyze the gearing ratios.

What is the math equasion??
How about running the 72/20 with the 5700/3s and see how you like it... But be VERY careful with heat.
I just ordered two fans for my ESC/Motor, but i'm not sure if i'll just gear it down or put the fans on.

I figured the 5700/3s would have been faster then a 7700/2s, but i guess you would have to try it with the same gearing on both to tell.



You can read this to find out more about FDR and the equation.
http://www.rcdriftnetwork.com/net/ev...al-drive-ratio

This will also tell you what your FDR is....
You need to know what your car's Transmission (internal) ratio is. On a TC4 it's 2.50:1

http://www.gearchart.com/index.cfm?f...=chart.create\

This also tells you what Spur/Pinion will give you certain FDR's as well (Hence chart)

ORIGINAL: Access
I was running a very similar setup in my TC4 once. 5700 motor, 3s LiPo. The LiPo was a maxamps 3s 4000mAH (this was 2+ years ago).
http://www.youtube.com/view_play_lis...9143C64687ABE9
I started out at 19/78 and eventually moved up one or two teeth at a time to 25/75. By the end I had a powerful 8 watt, 14000RPM 40mm fan blowing air to keep the ESC and motor cool. With 25/75 I could hit a reliable 65mph, confirmed with a radar gun. 19/78 it would top out around 54mph.

I ignored the Higher/Lower FDR thing. I found it was absolutely useless in practice. The car had monster acceleration no matter how I geared it. I prefered the 19/78 gearing b'cos with 10 'punch control' I could floor the throttle from a dead stop and not lose traction. When geared higher, the punch control simply didn't have the range to let it accelerate without losing traction if I floored it.

If you have a batter that can provide enough current, your only concern when gearing is the temperature of the motor and ESC. If they are not too hot, keep increasing it to your hearts content. I don't know when you'll start to noticeably limit your acceleration but I was running 25/75 and my acceleration was basically beyond what the tires could handle.

There is no reason to run 4s LiPo with a 5700 motor. Unless you are drag racing. The bearings are made for ~65000RPM. Their newer motors might be able to handle 80,000RPM or so, due to better bearings, but those are just things you hear.
So 25/75 + 5700/3s gave you around 65MPH hmmm
How did you like the 18/78 ? Did you ever clock that?

So if i want to break the 65MPH mark, would i need to get a 7700K motor and run 3s or bigger?
Or can i get the 5700K motor to run faster then 65PMH?

If i can clock the car at around 65mph i honestly think I'll be happy haha..

I guess i'll be installing those Fan's, after all.
I'm also looking at getting a Radio with Telemetry to keep track of temps. Right now i do the touch test lol.
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Old 03-27-2009, 11:14 AM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

So if i want to break the 65MPH mark, would i need to get a 7700K motor and run 3s or bigger?
Or can i get the 5700K motor to run faster then 65PMH?



According to castle...you cant run the 7700 on 3s. I spoke to them and they stated the motor would fly appart.

You have 2 choices to get to 65 MPH

First need a great pack, Like SMC or Trakpower or Polyquest.. 5000 25-30c
On 2s with the 7700 motor you need to gear 72/19 and up the pinion of you want....but heat will probaby be an issue

On 40-4500 mah 3s 25-30c with the 5700 motor you need to gear like 75/20

check heat all the time
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Old 03-27-2009, 11:43 AM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

ORIGINAL: fergup1
On 2s with the 7700 motor you need to gear 72/19 and up the pinion of you want....but heat will probaby be an issue

On 40-4500 mah 3s 25-30c with the 5700 motor you need to gear like 75/20
First, the 19/78 speed of 54mph was also confirmed with a radar gun.

If you are chasing speed the 3s 5700KV setup should be a tad more efficient than the 2s 7700KV setup. The only time you really want those high-KV setups is when you are trying to go as fast as possible on 2s. More efficient means it runs cooler, which is what you want.

You need both powerful fans and good heatsinking to keep things cool enough. The CM36 motors are not exactly the best motors out there. Maybe in the future Castle will take what it learned when designing their 1/8th scale 'Castle-Neu' motors and roll that back into their 1/10th scale motors. Then you could probably hit 80+ easily.

http://www.youtube.com/watch?v=hFemI...e=channel_page
This was one of my earlier cooling setups.
Not quite as good as the one with the fan mounted horizontally (sucking from the ESC and blowing to the motor) but still somewhat effective.
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Old 03-27-2009, 12:01 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)


ORIGINAL: fergup1

So if i want to break the 65MPH mark, would i need to get a 7700K motor and run 3s or bigger?
Or can i get the 5700K motor to run faster then 65PMH?



According to castle...you cant run the 7700 on 3s. I spoke to them and they stated the motor would fly appart.

You have 2 choices to get to 65 MPH

First need a great pack, Like SMC or Trakpower or Polyquest.. 5000 25-30c
On 2s with the 7700 motor you need to gear 72/19 and up the pinion of you want....but heat will probaby be an issue

On 40-4500 mah 3s 25-30c with the 5700 motor you need to gear like 75/20

check heat all the time
I'll give the 75/20 a try. Thanks

ORIGINAL: Access
First, the 19/78 speed of 54mph was also confirmed with a radar gun.

If you are chasing speed the 3s 5700KV setup should be a tad more efficient than the 2s 7700KV setup. The only time you really want those high-KV setups is when you are trying to go as fast as possible on 2s. More efficient means it runs cooler, which is what you want.

You need both powerful fans and good heatsinking to keep things cool enough. The CM36 motors are not exactly the best motors out there. Maybe in the future Castle will take what it learned when designing their 1/8th scale 'Castle-Neu' motors and roll that back into their 1/10th scale motors. Then you could probably hit 80+ easily.

http://www.youtube.com/watch?v=hFemI...e=channel_page
This was one of my earlier cooling setups.
Not quite as good as the one with the fan mounted horizontally (sucking from the ESC and blowing to the motor) but still somewhat effective.
What Heat sink and fan is that? Do you recommend it for my setup?

I'm going to stick with the 5700K/3s since i already have it. I will make sure to keep it as cool as i can..
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Old 03-27-2009, 12:33 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

ORIGINAL: TomTomTuning
What Heat sink and fan is that? Do you recommend it for my setup?

I'm going to stick with the 5700K/3s since i already have it. I will make sure to keep it as cool as i can..
http://search.digikey.com/scripts/Dk...me=259-1301-ND
Fan - this is actually two fans put together. The combination is 16W, I seperated them as I only needed one.
It's a 12V fan so you should wire it directly to your 3s LiPo. It's one of the most high-power, high-pressure fans available for its size, much more effective than those dinky little 30mm x 10mm fans people use but also noisy and power-hungry.

http://www3.towerhobbies.com/cgi-bin...?&I=LXJHA7&P=7
Heatsink
With the more advanced cooling setup, I actually built a thin lexan 'exhaust shroud' to contain the air and keep it close as it blew over the heatsink. Rather than have the air go all over the place once it is exhausted by the fan.
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Old 03-27-2009, 01:06 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

ORIGINAL: Access

ORIGINAL: TomTomTuning
What Heat sink and fan is that? Do you recommend it for my setup?

I'm going to stick with the 5700K/3s since i already have it. I will make sure to keep it as cool as i can..
http://search.digikey.com/scripts/Dk...me=259-1301-ND
Fan - this is actually two fans put together. The combination is 16W, I seperated them as I only needed one.
It's a 12V fan so you should wire it directly to your 3s LiPo. It's one of the most high-power, high-pressure fans available for its size, much more effective than those dinky little 30mm x 10mm fans people use but also noisy and power-hungry.

http://www3.towerhobbies.com/cgi-bin...?&I=LXJHA7&P=7
Heatsink
With the more advanced cooling setup, I actually built a thin lexan 'exhaust shroud' to contain the air and keep it close as it blew over the heatsink. Rather than have the air go all over the place once it is exhausted by the fan.
Pic's of said shroud?
The fans obviously blow away from the heat sink correct (like a CPU heatsink/fan)?

Should i put a less power hungry fan on the ESC as well?


PS: I really appreciate the help. From you and fergup1
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Old 03-27-2009, 01:27 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

I don't have pics as that setup has since been converted to a racer. This was quite a while, 2+ years ago.

The fan was positioned between the ESC and motor, it sucked air from the ESC and blew it onto the motor. This constant airflow kept both pretty cool. The motor was by far the hotter of the two. I had tried different permutations of holes in the body, etc. to cool (instead of the fan) but I found anything else would throw of the handling.
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Old 03-27-2009, 01:35 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

YR has some decent Heatsink/fan combo's.
http://www.yeahracing.com/catalog/fo...c-179_180.html

I was thinking about going with something like this.



Here is what my car looks like currently.



I would put my ESC next to the motor, which would place the second fan over the ESC (i guess that's what it's meant for).
And then just put my Receiver next to that or on top of the servo
But i don't know if it will work with how the the cables come out of the motor.


Another question. Should i not cut my body to allow air flow while moving? Will that generate lift some how and cause it to be unstable?
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Old 03-27-2009, 02:37 PM
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Default RE: I want to go faster!! (TC4 & Mamba 5700K)

Don't know about those heatsinks, they look like they might not have enough exposed area, plus the ideal way to use a heatsink is to blow air past or over the heatsink (ie. using a shroud to 'shape' the air) rather than just blowing 'at' a heatsink. If you're blowing air 'at' a heatsink, you're depending on pressure to push it out of the way, as you increase the strength of the fan, you fight yourself more and more.

When I was cutting holes in the body It would disrupt the right-left steering at high speeds. It was really annoying so I gave up on that.
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Old 02-10-2018, 09:15 AM
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Have you progress? what speed?
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