ppc
M Go Blue
That's the function of the thermostat not the cooling fan.
Electric Fan worth it?
- Thread starter nhall80
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That's the function of the thermostat not the cooling fan.
Outsane
Supporting Vendor
The oem fan has a thermo clutch and is mostly spinning free until the motor heats up and the fan engages.
The fan is only one part of how a cooling system exchanges heat. A system can be designed to have zero forced airflow and still function well. The factory radiator is designed around the CFM flow rating of the engine driven fan. If you want electric fans you can spec a much more efficient heat exchanger with lower CFM requirements that electric fans work well with. This is how almost every vehicle in the last ten years does it.
I have been seriously contemplating removing the fan clutch and replacing with electric fans.
Many years ago, I built a 69 Chevy K1500 and installed a 350 that had been modified. Bored 0.060" over, ported, polished, balanced, and was about 375 HP. At that time, the only "fan technology" was a flex fan, where the blades flexed and flattened out with higher RPM, to "reduce drag". The fans always roared.
So, I installed an electric fan from a 1985 Chevrolet Citation and used a thermal switch in the upper hose of the radiator.
Even with the SBC being bored and working it hard, I NEVER had any overheating issues. I also installed a switch and relay that I could bypass the thermal switch and turn it on ahead of time if I knew I was going into a hard working situation or if the thermal switch failed.
I noticed an increase in butt-dyno as well as what appeared to be faster rev up/down like a throttle burp. Less mass to rotate.
Fast forward and a friend of mine from college ended up working for GM and part of their research is to completely remove the mechanically driven fan and replace it with either electrically driven fan or use the pressure from the PS pump and drive a hydraulically driven fan.
As it turns out, the hydraulically driven version did not pan out due to extremely high pressures and heat build-up.
The electric version took over, but they had to balance the heat load of the engine and the radiator design as well as the cross-sectional area of the grille.
They would install a design, then run the engine in the one-one gear ratio of the transmission, go to WOT, then dyno it down to 70 MPH. The engine had to maintain cooling under these conditions. Mind you, this truck was sitting still in a dyno room so there was no additional airflow other than the fan and cooling system could generate.
SO, for my LC I will start looking at what vehicles that currently use cooling fans and in what manner. I will go for something that is very common (IE: Dodge Caravan / Toyota Camry) so it is readily available.
I know my wife's 2009 Chrysler TC runs normally at 213°F. This scared me when I first installed the UltraGauge. I've seen it regularly as high as 226°F.
So, I figure that an electric fan that can keep this hot-blooded engine under control may be close. I will look at design, shrouding, and speeds. Them I would install them accordingly. I will place the fan near the upper left corner of the radiator since this area has the highest temperature differential from the cooling air and the coolant temp. This will make it easier to remove heat load from the engine the fastest.
Is this a scientific approach? IDK. Just kind of a redneck, world experience and I'll change it if needed. Of course, it may take me YEARS to get to this point, just because I have so many other things to do and maintain in the mean-time.
Many years ago, I built a 69 Chevy K1500 and installed a 350 that had been modified. Bored 0.060" over, ported, polished, balanced, and was about 375 HP. At that time, the only "fan technology" was a flex fan, where the blades flexed and flattened out with higher RPM, to "reduce drag". The fans always roared.
So, I installed an electric fan from a 1985 Chevrolet Citation and used a thermal switch in the upper hose of the radiator.
Even with the SBC being bored and working it hard, I NEVER had any overheating issues. I also installed a switch and relay that I could bypass the thermal switch and turn it on ahead of time if I knew I was going into a hard working situation or if the thermal switch failed.
I noticed an increase in butt-dyno as well as what appeared to be faster rev up/down like a throttle burp. Less mass to rotate.
Fast forward and a friend of mine from college ended up working for GM and part of their research is to completely remove the mechanically driven fan and replace it with either electrically driven fan or use the pressure from the PS pump and drive a hydraulically driven fan.
As it turns out, the hydraulically driven version did not pan out due to extremely high pressures and heat build-up.
The electric version took over, but they had to balance the heat load of the engine and the radiator design as well as the cross-sectional area of the grille.
They would install a design, then run the engine in the one-one gear ratio of the transmission, go to WOT, then dyno it down to 70 MPH. The engine had to maintain cooling under these conditions. Mind you, this truck was sitting still in a dyno room so there was no additional airflow other than the fan and cooling system could generate.
SO, for my LC I will start looking at what vehicles that currently use cooling fans and in what manner. I will go for something that is very common (IE: Dodge Caravan / Toyota Camry) so it is readily available.
I know my wife's 2009 Chrysler TC runs normally at 213°F. This scared me when I first installed the UltraGauge. I've seen it regularly as high as 226°F.
So, I figure that an electric fan that can keep this hot-blooded engine under control may be close. I will look at design, shrouding, and speeds. Them I would install them accordingly. I will place the fan near the upper left corner of the radiator since this area has the highest temperature differential from the cooling air and the coolant temp. This will make it easier to remove heat load from the engine the fastest.
Is this a scientific approach? IDK. Just kind of a redneck, world experience and I'll change it if needed. Of course, it may take me YEARS to get to this point, just because I have so many other things to do and maintain in the mean-time.
