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Old 02-13-2013, 02:32 PM   #1
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Default motor fan cooling

is the fan supposed to suck in cool air to the motor or blow out hot air from the motor? what is the best positioning of a fan?
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Old 02-13-2013, 03:05 PM   #2
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You'll get the best results with the fan blowing air onto the motor.
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Old 02-13-2013, 09:10 PM   #3
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8mm spacing from fan to motor
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Old 02-13-2013, 11:32 PM   #4
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Originally Posted by hanulec View Post
8mm spacing from fan to motor
Why 8mm? Behind motor or on top? I am still playing around with this! It seems I always get my highest temps on top of motor and closer to pinion side. I see alot of guys with fans behind motors and away like probably 8mm or so. Is there a theory behind this position?
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Old 02-14-2013, 12:49 AM   #5
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on transverse mounted motors such as on an xray t4 or trf417, air flow from the chassis driving direction provides sufficient airflow on the front & top of the motor when the car is moving forward. In effect this airflow creates negative (recirculating) air pressure on the back of the motor, resisting fresh airflow therefore generating compounded heat on the back of the motor. mounting the fan directly on the back of the motor eliminates negative air pressure & provides sufficient airflow where its needed.

for most racers mounting directly behind the motor is most likely due to the ease of installation & even possibly an attempt to keep the center of gravity as low as possible.

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Why 8mm? Behind motor or on top? I am still playing around with this! It seems I always get my highest temps on top of motor and closer to pinion side. I see alot of guys with fans behind motors and away like probably 8mm or so. Is there a theory behind this position?
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Old 02-14-2013, 01:25 AM   #6
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Quote:
on transverse mounted motors such as on an xray t4 or trf417, air flow from the chassis driving direction provides sufficient airflow on the front & top of the motor when the car is moving forward. In effect this airflow creates negative (recirculating) air pressure on the back of the motor, resisting fresh airflow therefore generating compounded heat on the back of the motor.
Good info!

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mounting the fan directly on the back of the motor eliminates negative air pressure & provides sufficient airflow where its needed.
Which direction should the fan blows, when mounting at the rear side of the motor.
The air should be blowing towards or away from the motor? Why that direction?
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Old 02-14-2013, 01:44 AM   #7
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most racers blow towards the motor, against aerodynamic airflow.

any aerodynamics expert would beg to differ. does it matter? no. this scale of racing defies most real world theories.



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Good info!



Which direction should the fan blows, when mounting at the rear side of the motor.
The air should be blowing towards or away from the motor? Why that direction?
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Old 02-14-2013, 03:21 AM   #8
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Quote:
Originally Posted by R1wurks View Post
on transverse mounted motors such as on an xray t4 or trf417, air flow from the chassis driving direction provides sufficient airflow on the front & top of the motor when the car is moving forward. In effect this airflow creates negative (recirculating) air pressure on the back of the motor, resisting fresh airflow therefore generating compounded heat on the back of the motor. mounting the fan directly on the back of the motor eliminates negative air pressure & provides sufficient airflow where its needed.

for most racers mounting directly behind the motor is most likely due to the ease of installation & even possibly an attempt to keep the center of gravity as low as possible.
because science!
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Old 02-14-2013, 04:14 AM   #9
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when i set my tc up i mounted the fan behind the motor on the chassis with servo tape (blowing on to the motor). i took off the pinion and moved the motor to the most reward position, then used a 8mm shim to set fan spacing from the motor. this way i know no matter what gearing i use the fan will not be an issue. one thing to keep in mind, where ever you put your fan be aware of the surrounding parts of the car, like if there's any screws you need to get to, etc... one thing that would suck is tearing the fan off the car every time you needed to make an adjustment.
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