[Joe G]

Well, guys I,m changing tactics for my fan problem.
I'm looking at electric fans to replace the stock clutch fan setup in my 69 396. I have been searching the posts and see a lot of different fans being used.

My question is about clearance. I have 3 1/2" from radiator to end of water pump shaft. (4 core BB US Radiator, 2 3/4" thick) . Most of the fans I have seen in Jegs and Summit are thicker. I went to the Vintage web site to check out Spal fans and they are thicker as well.

Also, the fans in Summit and Jegs state they are good to about 250 HP which seems too low to be useful.

For you guys that are using these, what radiator and what is your clearance? Where did you get them?
Maybe my car is just weird?

Thanks again for your patience!

Joe



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69 396 w/SS Trim
Badboatdude@CS.com
69 Pics http://albums.photopoint.com/j/Album...559&a=11674961

[CA420]

Spal makes a 16" fan that will work, mine is 2 1/2 inches deep and moves some air.

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68 RS, Ash Gold,pwr windows,Hounds tooth,355/T350,Autometer guage pod

[boodlefoof]

I often wondered about those ratings they use on the fans. A mechanic friend of mine told me that the horsepower rating means it will cool an engine that is constantly putting out that power. For example, if you have a big block that cruises at 3000rpm and puts out 300 horses at that rpm, then the fan wouldn't be sufficient to cool it for extended periods of time. However, if you cruise the same big block at 2000rpm, where it only puts out 200 horses, it would be ok. That is just what I have heard, I don't know if it is exacly right.

[oger]

Joe aren't cars wonderful I gave up on clutch fans and only use flex fans. I know they use more power but the clutch doesn't die in traffic when its 105 degrees outside. You can buy different length spacers to put the fan where you want it and the clutch unit doesn't stick out in front to hit the radiator.

[ilbl8]

first off the only way to rate a electric fan is by CFM. that rating is with no restriction infront of the fan. a radiator core will drop the CFM rating about 15% to 30%.

most electric after market fan's are set up to be mounted to the radiaor core. this is not good as the core is not ment to have that type of load on it, and the fan should be about 1/2" to 2" away from the core to help prevent a fan blad stall. a stall is when the blad can not bite and move the air because there is no air to move.

IMHO flex fan's are a bomb waiting to go off, do a search on them and you will see why i think this way.

every OEM electric fan has a big shroud on it, it will cover about 80% of the radiator core on the car it was used on. it will also have the blad's about 1" from the core. that is to make the fan flow the most air over the most surface area of the radiator core and to make sure the fan dose not stall.

if you do a search you will find a lot of people not getting proper cooling just mounting the fan to the radiator core, this is because it can not pull air over a big enough area of the core and the blad's are stalling out.

IMHO a 16" electric fan mounted to a custom shroud flow's perfict for most SB and BB motor's with A/C. i did this to my blazer, here is a pic of it on the radiator. i had the shroud made at a sheet metal shop for $42.00, the fan cost me $65.00 and the thermo switch i put in the head cost me $20.00. i had a relay and wire all ready to wire it up. i all so taped in to the A/C circit to turn the fan on with the A/C. i had to use a diod to isolate the feed to the fan so the A/C would still work.

i can turn the fan on and feel the flow of air from the edge of the grill. it flow's about as much as my stock clutch fan did whith the clutch locked up at 2000 RPM.

http://y42.photos.yahoo.com/bc/ilbl8...src=ph%26.view =t]http://y42.photos.yahoo.com/bc/ilbl8/vwp?.dir=/car+stuff&.src=ph&.dnm=fan.JPG&.view=t&.done=http% 3a//y42.photos.yahoo.com/bc/ilbl8/lst%3f%26.dir=/car%2bstuff%26.src=ph%26.view=t



[This message has been edited by ilbl8 (edited 04-13-2001).]

[boodlefoof]

Oger,

I am sure Joe will tell everyone how much he hates flex fans.... they are what got him into his current situation....

[Joe G]

You're right about that, Boodlefoof!!! No flex fans for me.
(Where does boodlefoof come from?)

Thanks for the help. I got the new clutch fan straight and it's working now, so I think I'll just drive it for a while (for a change!).

Now if only I can keep the water pump belt on! It comes off every time I go over 5000 rpm.

I guess it just never ends.....

Joe

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69 396 w/SS Trim
Badboatdude@CS.com
69 Pics http://albums.photopoint.com/j/Album...559&a=11674961