Interesting cooling fan arrangement

[C9]

While perusing the Buick V8 board I came across this more than interesting comment about fans.



"One time when I didn't have a shroud, I "stacked" two 17-inch flex fans- one fan bolted directly to the water pump flange, then a 3" spacer, then a second fan. Having two fans like this simulated a shroud, and pulled mega-airflow to boot. In fact that setup pulled so much air at idle, that I could not pour water into the radiator without the water being sucked all over the engine!"



Granted, most of us couldn't fit such an arrangement in our cars, but if a guy could....

The entire discussion is here:
http://www.v8buick.com/showthread.php?t=35850&page=2
[/quote]

[Charlie Chops 1940]

Jay...that link gives a lengthy discussion about Q-jets. Does the thread have a picture or just the description?

Charlie

[C9]

Jay...that link gives a lengthy discussion about Q-jets. Does the thread have a picture or just the description?

Charlie

Just the comment as noted above.

Some propellor fighter aircraft had two props, but they were contra-rotating.
I think what's happening here is that he has in effect a ten bladed fan.
(Assuming the two flex fans were 5 blades each.)

Reminds me of my friends less than brilliant attempt at putting two radiators in one pickup.
The 352 that replaced the broken 272 ran hot so he figured stacking radiators would do the trick.
to that end I made him some 'Y's' so he could connect them, but what he didn't figure on was the hot air from the front rad dumping into the second rad.

Lemme try the link and see where it goes.

[C9]

Sorta weird.

I copied the addy from the addy bar - copy and paste.

Anyhoo - here's one that should work.

http://www.v8buick.com/showthread.php?t=60809

[HOTRODSRJ]

In fact that setup pulled so much air at idle, that I could not pour water into the radiator without the water being sucked all over the engine!"

This statement alone should tell you that the fans where NOT pulling the air THRU the radiator because of no shroud. They are sucking air from everywhere, even over the top of the radiator as explained by this statement.

Actually more blades means more air, but most flex fans are not real good producers of airflow anyhow, so two are better than one.  Also, more air.....more hp eaten alive.  I would stick with the Derale heavy duty series flex and a shroud if you can...or a good electric setup.  At idle with my 69Camaro and a shroud with a 17" Derale produces over 2400 cfms of airflow (at 950 idle speed). This was measured by static pressure over a given area. I worked on this to get it to that number. Pretty good system I'd say.

[C9]

In fact that setup pulled so much air at idle, that I could not pour water into the radiator without the water being sucked all over the engine!"

This statement alone should tell you that the fans where NOT pulling the air THRU the radiator because of no shroud. They are sucking air from everywhere, even over the top of the radiator as explained by this statement.

Actually more blades means more air, but most flex fans are not real good producers of airflow anyhow, so two are better than one.  Also, more air.....more hp eaten alive.  I would stick with the Derale heavy duty series flex and a shroud if you can...or a good electric setup.  At idle with my 69Camaro and a shroud with a 17" Derale produces over 2400 cfms of airflow (at 950 idle speed). This was measured by static pressure over a given area. I worked on this to get it to that number. Pretty good system I'd say.

Good point on air movement vs. HP.
Even so, giving up some HP is worth it if you can drive the car in hot weather....

I run Haydens - got a Derale in the box - cuz they're set back on the hub and Derales are not.
The Haydens help in the front clearance dept. with the big block Buick in the 32.

Anyhoo - I used to recommend your well written article on fans and cooling to others, but when my old computer died I lost the address.

Is the article still on the Internet?
And if so, may I have the address.

[Crosley.In.AZ]

I noticed on the 2005 light duty 1/2 ton GM trucks & Avalances that they now have dual electric fans on the radiator.

they could possibly be some strong fans to meet the needs of a pickup.

I prefer mechanical fans on my trucks