Radiator Size ????
Slowly block off the electric fan and it will start to slow down. That is a condition of stall.
And what does it do when it starts to stall? Yeah, you guessed it, it's output is reduced.
So please, don't go telling me what it isn't. ok?
You can talk all the CFM you like but under how many inches of h2o is that CFM being achieved?
No point having a fan that has 4500 CFM free flow, just to find it only has 1000CFM once it's put up against the radiator.
I'm not going to bother getting into the nuts and bolts of cooing systems and how to effectively set them up, because this place does not pay my bills, but I can see from this thread that most people have zero idea how to do it.
Yeah so if you blocked off a radiator the electric fan behind it would definitely lose output, but it wouldn't be because of the rpm the blades were spinning. You might actually get a stall, but that would allow the rpm to remain the same/similar while the output reduced. You're not going to bog an electric motor like that in the real world. The rpm might vary slightly with the air resistance, but the picture you're painting of the motor winding down is not at all accurate.
As far as the rated CFM, on that we agree. You're at the mercy of how the company rated its fan, the published spec is not likely to be under the same conditions as what you'll get mounted to a radiator. But unless you're going to buy a dozen fans and test them yourself, well, you're SOL. So, all you can really do is consider the published CFM and go from there. If the rated CFM is less than the mechanical fan you're replacing, you have no chance at all. If it's higher, well, it should work as long as the manufacturer hasn't spoofed their numbers. But that's true of everything isn't it?
Most people don't have an idea of how to set up a cooling system, or even the things they need to be considering, which is why these threads always devolve into guys yelling about bigger tubes or how all electric fans suck because they couldn't get theirs to work. But I don't think you're going to dazzle me with the "nuts and bolts" either, given the inaccuracies you've already posted.
I agree there BUT... look at the size of the radiator for a V6 as compared to that of a 60s 70s V8. The V6 is huge compared.
There's a lot that goes into that. The power per cubic inch of a modern V6 is much higher than the old V8's, which means more heat in a smaller package. There's also the design of the car. Like if you look at the Ford Contour V6 I pulled my electric fans from you'll see they have a TINY grille opening, and the engine compartment is packed solid end to end. So, even though the engine is smaller, the fans are pretty awesome.
