So I did a PDI on a 2010 and noticed something...
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They also said that they moved a lot less air than mechanical fans and didnt last as long.
I guess the way they figure it is if you have a mechanical fan moving air at 5000rpm and it's pulling 10hp a electrical fan which is also moving 5000cfm needs the same amount of HP to get that amount of CFM. Like they say. You cant get something from nothing. The engine will have to put out at least 10hp to give the electric fan enough power to move 5000CFM. If they could then all cars would be using gas engines to drive a electric motor that drives the wheels. They already do this but at massive decrease in HP/TQ. Same as the electric fan nearly always needs to run after you switch of the engine because they cant cool like mechanical fans.
But perhaps the laws of physics don't apply to engine fans
I guess the way they figure it is if you have a mechanical fan moving air at 5000rpm and it's pulling 10hp a electrical fan which is also moving 5000cfm needs the same amount of HP to get that amount of CFM. Like they say. You cant get something from nothing. The engine will have to put out at least 10hp to give the electric fan enough power to move 5000CFM. If they could then all cars would be using gas engines to drive a electric motor that drives the wheels. They already do this but at massive decrease in HP/TQ. Same as the electric fan nearly always needs to run after you switch of the engine because they cant cool like mechanical fans.
But perhaps the laws of physics don't apply to engine fans
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Yeah for sure cost and ease of install are other feature ford liked but noise is more to do with the CFM the fan operates over the design. The only way the electric fan would be quiter is if it is moving less air a minute and thats prob why they always run after you get out of the vehicle.
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Yeah for sure cost and ease of install are other feature ford liked but noise is more to do with the CFM the fan operates over the design. The only way the electric fan would be quiter is if it is moving less air a minute and thats prob why they always run after you get out of the vehicle.
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From: lost vegas
they stay on a moment after the vehicle is shut off because they are just waiting to be told to shut off by the ECM due to 2 reasons. 1 being that computer doesn't just shut off, it has an order it does it in or, 2. it stays on because the vehicle is set to cool the radiator to a certain temp.
why would you want mech over elect? in traffic at idle your getting very little air with the clutch fan, but with electric you get a large amount of air. and at speed, you don't need fans too much anyway.
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From: Burleson, Texas
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I always thought the Mec fan disconnected from the engine at higher speeds due to the fan not being need and it produces more than enough cooling at lower speeds due to the high CFM. If it didnt then i guess we would have over heating issues in cars with mec fans.
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the fan clutch does disconect when its not needed. mechanical fuel pumps worked back in the day too...there is always room for improvement.
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Yeah there's def room for improvement. I have just never understood the claims of an increase in HP from such silly little things. Snake oil comes to mind. This is like the CAI and exhaust debates on increasing power. I have never found they do anything other than let lots of dust into engine and make loud noise
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Yeah there's def room for improvement. I have just never understood the clims of an increase in HP from such silly little things. Snake oil comes to mind. This is like the CAI and exhaust debates on increaseing power. I have never found they do anything other than let lots of dust into engine and make loud noise
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they have their place...and that place is not on a diesel work truck. Lots of dusted engines go through my shop because of these CAI systems.
