No, that's not my assumption.
Mike, sorry if I misread your prior comment. I could read it two ways and wasn't sure how you meant it, which is why I said "if that was the intent of your comment".
I've had discussions with the design engineers from Spal and another major fan manufacturer (forgot the name at the moment) at previous SEMA shows. What they told me was the "modern" design fans are superior to the old designs in pretty much every aspect. So given the same diameter, RPM, drive motor, etc, the modern style will move more CFM, draw less current, make less noise, etc, than the old type. And another interesting thing is noise isn't necessarily a function of CFM; a higher CFM does not necessarily make more noise, and more noise does not necessarily mean more CFM. Noise has more to do with the design of the blade. That's not to say if you took the same fan and ran it faster (increased CFM) that it wouldn't make more noise - it would (one reason Spal offers the same size fan with different CFM's, one has less noise). But the older style fans have much higher noise levels for the same CFM compared to modern ones. Another example of how fan blade design effects noise is the "straight" blade vs "curved" ('S') blade option on modern fans - one if quieter.
Maybe what was determined was that the Fiat fan performs better than the Chinese fans that came on the aluminum rads? (I could believe that.)
That was one point I was trying to convey earlier. Not all 'modern' fans are necessarily efficient, so some will move less air than the stock Fiat fans.
Which fan is better - the OEM Fiat? Or one of the currently available, commonly used, fans available from suppliers such as Spal?
Depending on the particular model of modern fan chosen, I'd certainly say the newer design fans are better than the stock fans. But as the last comment just said, that does not include
all 'modern' fans.
To make a reasonable comparison I think it would be important to have actual numbers. I understand how difficult it may be to measure the performance of the Fiat fans, and I appreciate someone's attempt.
I completely agree, which was what I was trying to say about the old thread on this topic. They attempted to get some idea of the stock fan's CFM. But it would be ideal to have the actual true CFM rating and compare it to all of the choices of modern fans to find better replacements. However it gets even more complicated than that unfortunately. I've been told some fan manufacturers use non-standard methods to measure their product's CFM. That allows them to advertise higher performance levels, although they may not actually be accurate compared to other testing methods. So you may not be getting what you think. Typical of modern business practices. I'd trust a top manufacturer with a known repetition more than some others. Which tends to also mean higher purchase prices.
There is a relatively new fan manufacturer that was started by a couple of former Spal engineers to offer some competition in the marketplace. Their fans are basically clones of Spals but at a lower price point (which does not mean 'inexpensive'). I posted about them in one of the related threads previously, but I'd have to look up the name again. However Spal isn't the only designer of good fans.