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What temperature is motor getting hot at?
I run 8s 1650 34/34spool with dual fans no heat issues
Did you try going up on pinion?
Are you in 6 or 8s esc?
I run 8s 1650 34/34spool with dual fans no heat issues
Did you try going up on pinion?
Are you in 6 or 8s esc?
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Oh yes another limitless overheating! 
I do know you can get water cooled for rcs whether you can have watercooling on your rc depends on how creative you can be.
Guess Arrma should have installed a heat sink and dual fans from the factory. Glad I sold it now- Thread starter
- #5
I can get very creative. I come from racing drones and PC builds originally. Running 8s esc. 8s standard spectrum setup. Speed running and street bashing. Heats up faster trying to drift.
I'm thinking of trying to 3d print some intakes for esc and cut holes in body.
But that only really help while moving straight in theory. Not as much when going slower bashing around parking lot.
Mostly looking for ideas or if someone has already done it.
Saw one guy on YouTube totally change how everything was mounted but wasn't very elegant of a solution.
Arrma seems to waste alot of space under limitless body.
EDIT: I don't have a way to find temp but def too hot to touch.
Doing some maths here. Not removing space for servo, center brace and motor, there is 200 cubic inches of space under the hood.......
I'm thinking of trying to 3d print some intakes for esc and cut holes in body.
But that only really help while moving straight in theory. Not as much when going slower bashing around parking lot.
Mostly looking for ideas or if someone has already done it.
Saw one guy on YouTube totally change how everything was mounted but wasn't very elegant of a solution.
Arrma seems to waste alot of space under limitless body.
EDIT: I don't have a way to find temp but def too hot to touch.
Doing some maths here. Not removing space for servo, center brace and motor, there is 200 cubic inches of space under the hood.......
Last edited:
StephenSchandelmayer
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Big ole fans baby. Run on extra 3s battery
https://www.ebay.com/itm/Sanyo-Denk...2349624.m46890.l49286&mkrid=711-127632-2357-0
https://www.ebay.com/itm/Sanyo-Denk...2349624.m46890.l49286&mkrid=711-127632-2357-0
I can get very creative. I come from racing drones and PC builds originally. Running 8s esc. 8s standard spectrum setup. Speed running and street bashing. Heats up faster trying to drift.
I'm thinking of trying to 3d print some intakes for esc and cut holes in body.
But that only really help while moving straight in theory. Not as much when going slower bashing around parking lot.
Mostly looking for ideas or if someone has already done it.
Saw one guy on YouTube totally change how everything was mounted but wasn't very elegant of a solution.
Arrma seems to waste alot of space under limitless body.
EDIT: I don't have a way to find temp but def too hot to touch.
Doing some maths here. Not removing space for servo, center brace and motor, there is 200 cubic inches of space under the hood.......
I think most peeps shop for server fans; not "RC fans".
As am sure you know, those are VERY good fans / move lots of air.
watercooling would maybe start to be a possibility for 5th scale and up + speed runs. but even at that am unsure how would secure / build such it can handle those crazy g-forces from crash / normal bashing. other wise I see the extra weight being too much until getting up to 5th scale.
for scale build purpose water cooling looks so cool imo (little radiator and fan and all lol)
whats more cooling motor is still via lots of heat transfer / are "just cooling" the can directly (meaning not like cpu / gpu cooling which is much more direct) don't let your experience with PC chip cooling give you intuition that more cooling esc / motor = more performance in same way.
you can cool the can of the motor to zero and still overheat it / spoil the magnets / spoil the insulator on the windings....paymind to the wattage headroom. for example I went 8s system to run 6s to avoid any heat concerns (of course temp is still a concern / something to keep an eye on). is hyperbolic example; you could gear down and achieve similar thing.
that said if you've tinkered with pc's / racing drones, you'll tinker with cooling and learn it. just read about heat and electric motors so know a bit of the "physics" / mechanical concerns of heat. with pc experience you already know of esc cooling (is same direct chip cooling) and there is no heat related performance concerns...just smokin' concerns lol
Diem Turner
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I don't think you want to add a water reservoir to your RC car having all that extra weight sloshing around potentially making the car unstable. On RC boats that are surrounded by a gigantic water reservoir that they don't need to haul around with them a water cooling system makes sense, but on a car? I concur with what @TL01magic said. Server fans is where it's at. Two 40mm fans even just running on 2S can move an impressive volume of air. On 3S they move sufficient amounts of air that they can easily levitate. I can recommend the website digikey.com. They're fast and they have a truly gigantic selection. I put two of these on a Powerhobby fan mount, added a 3-way switch so I can chose between off, 2S and F5 tornado.
 | 04028DA-12T-AK-HAQ 12-04028DA-12T-AK-HAQ-ND 40MM X 40MM X 28MM, 12VDC, W 4-W |
- Thread starter
- #9
Thanks for the tips I didn't consider the stuff about cooling the can still not cooling the important bits in the motor. I just got some fans from Amazon and a step up regulator to see if I can run them on the spectrum bec instead of another battery.
Was watching some videos about the cars aero and am going to do somethings. Anyone see any definitive data on cutting the front / rear wings down? Or cutting holes in body for venting? Not sure if get body is 100% requires for over 150mph runs
Was watching some videos about the cars aero and am going to do somethings. Anyone see any definitive data on cutting the front / rear wings down? Or cutting holes in body for venting? Not sure if get body is 100% requires for over 150mph runs
I think you get it but just so is clear the "Cool the can to zero and still overheat it." was VERY hyperbolic, but meaning to point out that there is still a heat transfer from the important bits; unlike with cpu/gpu or even ESC cooling.
airflow on motors makes a huge difference in how fast the motor can-can shed heat.
If a fan/heatsink is not enough, reducing the load(smaller pinion) is always the correct answer. An BL motor is not like a cpu. If it gets too hot for the application, you have to go bigger.
Cutting the front and rear is better for high speeds in terms of load. Yet with your current electronics, ~115mph will be your maximum speed.
Never go bashing with the car setup for top speed.
- Thread starter
- #13
So got some real data on a speed run today.
made about 5 good passes in a commuter lot about 1/10th of a mile wide. I can see where ill need maybe double that to get a solid run in.
That being said I got 89 mph peak.
Stock down force on the body fins.
Not enough heat during runs to kill it.
Once the lipos got low enough where i could tell I wasn't getting any real speed i decided to do some laps/drifting and everything cut off at 165F on the esc. the motor came in at 220F or so. I'm guessing the sensor is in the esc not the motor?
This is after I cut vents in body and added higher cfm fans.
Got some weird tire wear out of it. I think with the light bumps in the lot one tire was unloading a lot.
In terms of progression I think I'm at a good start/baseline. There is a lot of tuning to do with the aero and chassis this rig is literally out of the box a day ago.
Pay no attention to the lost shock mount covers when she decided to see if she could fit in the sewer drain at 30 mph.
A 89mph gearratio is not superfast in terms of speedrunning, but for bashing, especially with partially drained batteries (results in more amp draw), where you do not give the system any rest it will run hot quickly. Gear it down and you can...
Or upgrade the motor and esc. Both have a threshold of 4-5k Watts. Frequent bursting will heat things up even with half the wattage. A bigger motor and esc can deal with more whiles staying efficient (not generating excessive heat)
Spekrum does not measure temperature of the motor, the thermal/low voltage/ high amp protections all kick in based on what the ESC measures.
But ESC and motor are directly connected by 3 wires and will overflow excessive heat to each other. It can really help to put a high speed fan on both the esc and motor.
The vents are nicely done but will cause blowovers when you start doing 100+ speedruns.
The wear looks like you run a lot of camber (valid option) or just tire imperfection/balance that exposes the inner wall side to wear more during drifting
Or upgrade the motor and esc. Both have a threshold of 4-5k Watts. Frequent bursting will heat things up even with half the wattage. A bigger motor and esc can deal with more whiles staying efficient (not generating excessive heat)
Spekrum does not measure temperature of the motor, the thermal/low voltage/ high amp protections all kick in based on what the ESC measures.
But ESC and motor are directly connected by 3 wires and will overflow excessive heat to each other. It can really help to put a high speed fan on both the esc and motor.
The vents are nicely done but will cause blowovers when you start doing 100+ speedruns.
The wear looks like you run a lot of camber (valid option) or just tire imperfection/balance that exposes the inner wall side to wear more during drifting
- Thread starter
- #15
That's some really great input thank you. I haven't added any extra tuning on the suspension except droop to counteract the body roll and lifting of front tires. I
