Wow! Cash Loss On Radiator Tear. Fan Clearance Issues.

[ludwig]

These guys have high flowing fans. I think the CFM rating will be more important than the diameter. Check the 10" and 12" fans. They are quite shallow and flow a lot.

http://www.zirgo.com/products.lasso

 

[WhitePony]

Another possible idea would be 2 smaller fans mounted diaganally. That way the water pump pully would be in the center where the fans would be either narrower or not there at all:

This fan is 9" accross, and 2 1/2" deep. It pulls 1300CFM. A pair of them would be well over 2000CFM

I took a pair of 9" paper plates out to my stang and there should be plenty of room on the radiator.

Kris

 

[PLP6400]

I tried two 9" electric fans mounted diaganally last summer and the car overheated in traffic. The problem, I think was because only about 50% of the radiator core had air moving over it. With the 6 blade 15" factory fan it has never over heated. I do wish I could find a 14" or 16" electric fan that is thin enough to fit.

 

[ludwig]

Check the PAW (Performance Auto Warehouse) catalogue. They have several different large fans with depth specified. Unfortunately you have to order the catalogue. No web shop.

http://www.pawengineparts.com/

 

[WhitePony]

I thought about that too. It would take a bit of work, but you could make a shroud that covered the radiator face that was about 1/2" wide. Mount the two 9' fans on the shroud, then the air would pass through the entire radiator. This is basically the same idea that is used on the hi performance aluminum radiators:

Even adding the half inch, it should still have a low enough profile to fit. It would mean some work, but it should work good. You would not have any air spillage. Every CFM of air would pass through the radiator.

Kris

 

[Guest]

Pretty darn good idea. Too bad the machine shop is 90 miles away.

Yes, mustangs have more clearence than the falcons. The underhood space is larger, by how much, Im not sure.

 

[Fred]

WhitePony - Sorry to rain on your parade but that shroud won't work. You arn't actually pulling more air with a shroud when your fan is attached to the radiator. Shrouds are used when the fan is far enough from the radiator to pull air from the engine compartment instead of through the radiator. Also that much shroud will block air running down the road.

This is a subject debated a lot in flathead v8 groups. In a flathead the exhaust passages run for about six inches though the water passages, thus cooling becomes interesting (and why you can run a healthy overhead valve eight behind a stock flathead radiator). What you really want is a fan that pulls air like crazy when the car is not moving, and pretty much disappears when you get moving. Remember that a large fan is an obstruction to air flow when you are going down the road too. My father's '47 Ford pickup would cool nicely in 105 degree weather with a big four blade fan and a shroud, below 50 m.p.h. Get rid of the fan and shroud and it would cool above 30 m.p.h. but overheat running slower than that. The fan was about three inches from the radiator. The only flathead we have had that would cool all the time, no matter what, was a '41 pickup with a big six blade fan positioned about 1/4 inch from the radiator. The conclusion to this (too long?) story is that you need the biggest electric fan you can fit in your car, run off a thermostate, and ditch the water pump driven fan.

 

[ludwig]

See what you can do with a pusher, if there is more space in front of the radiator.

 

[Anonymous]

Nice thing about the electrics, is that you don't have to worry about the classic problem of overheating at stoplights and in slow traffic.

But you do need a higher amp alternator - ~80-100 amps will help a lot.

This fan is 9" accross, and 2 1/2" deep. It pulls 1300CFM. A pair of them would be well over 2000CFM

Tried them. They don't.

 

[WhitePony]

See what you can do with a pusher, if there is more space in front of the radiator.

He can't do that because of the AC condenser in front of the radiator.

WhitePony - Sorry to rain on your parade but that shroud won't work. You arn't actually pulling more air with a shroud when your fan is attached to the radiator. Shrouds are used when the fan is far enough from the radiator to pull air from the engine compartment instead of through the radiator. Also that much shroud will block air running down the road.

This is a subject debated a lot in flathead Vee-Eight groups. In a flathead the exhaust passages run for about six inches though the water passages, thus cooling becomes interesting (and why you can run a healthy overhead valve eight behind a stock flathead radiator). What you really want is a fan that pulls air like crazy when the car is not moving, and pretty much disappears when you get moving. Remember that a large fan is an obstruction to air flow when you are going down the road too. My father's '47 Ford pickup would cool nicely in 105 degree weather with a big four blade fan and a shroud, below 50 m.p.h. Get rid of the fan and shroud and it would cool above 30 m.p.h. but overheat running slower than that. The fan was about three inches from the radiator. The only flathead we have had that would cool all the time, no matter what, was a '41 pickup with a big six blade fan positioned about 1/4 inch from the radiator. The conclusion to this (too long?) story is that you need the biggest electric fan you can fit in your car, run off a thermostate, and ditch the water pump driven fan.

Hmmmmmm..... OK, well, why are there so many radiator fans out there with a design similar to the pics in my last post? I can see what you are talking about when you say that it could be an obstruction to airflow at speed though, when most of the cooling is being done passively by the air being forced in while you drive. But why are there so many high performance cars out there that use multiple fans with a partially blocked airflow? I mean, if it didn't work, they wouldn't exist. I'm not trying to be argumentitive, and I'm certianly not a thermal engineer, but that radiator is supposedly for high performance applications, and it has the same amount of blockage.

But you do need a higher amp alternator - ~80-100 amps will help a lot.

Good point. I hadn't thought about that. As part of my rebuild, I'm doing a chromed 100 amp alternator. Those dual fans may be too great of a constant current draw for a stock alt. I think most of those fans draw at least 5 amps, so a pair would draw at least 10. That's a significant percentage of a stock alt's output.



Kris

 

[Fred]

WhitePony - Sure many high performance cars have two electric fans. They ususally are on radiators that are about twice as wide as they are tall and the fans are side by side, or they are on radiators that are twice as tall as they are wide and the fans are one above the other. The more sophisticated setups use two thermal switches and turn one on before the other, say at 195, then the other at 205. None of them use shrouds. As I stated previously the point of a shround is to keep the fan from pulling air from inside the engine compartment. If the fan is too far back from the radiator air inside the enigne compartment can be pulled forward along the inner fenders, across behind the radiator, and back through the fan. This simply recirculates the air in the engine compartment. The farther from the radiator, the worse this becomes. You can visualize this by placing a box fan a few inches from a wall, pointing into the room. All the air pulled by the fan has to flow around the back of the fan between the fan and the wall before it is blown into the room. The same thing happens to a much smaller extent in an engine compartment. This is solved by placeing an obstruction between the edges of the radiator and the fan (a shroud) so that air cannot flow through that area, or by placing the fan so close to the radiator that there is no place for air to be drawn if from the side (attaching the fan directly to the radiator as in an electric fan or by making sure your engine driven fan is within 1/2 inch of the radiator, thus there is no point in installing a shroud with an electric fan that is attached to the radiator).

Anything that sits directly in front or behind the radiator block flow when you are running down the road. Even if the fan spins fast enough to move air at the same speed as the car is moving (which is highly unlikely above about 50 m.p.h. in most cars) if there are brackets that hold the fan to the radiator, the brackets block air. This is not much of a problem with one or two well designed electric fan(s) with (a) thin plastic support bracket(s). A shroud automatically shrinks the area that air can flow through to the diameter of the fan. If the radiator is a bit oversized and the fan opening on the shroud is very large this is not much of a problem running down the road. If you have a small diameter fan with a lot of blades and a shroud that fits that small diameter fan it might do a fine job of cooling you car at slow speed, but block too much of the air flow through the radiator while running down the road. The picture you posted looked to me like all of the radiator was blocked except just the area around the small electric fans. That is over half of the radiator blocked; you will not be able to drive down the road with that setup. What might work on a square radiator is four small fans, possibly with two thermal switches, one for the top two and one for the bottom two. This would probably be prohibitively expensive and would require a big amp alternator. The benifit of two thermal switches is that there is less electrical draw with two running, and on a cool day that my be all that is required. I hope I have written this clearly enought that it all makes sense. If you have any more questions please ask, Fred.

 

[WhitePony]

OK, I'm sold, it was a bad idea.

Here's a 16" fan I found on eBay that's only 2 1/2" thick.

http://cgi.ebay.com/ebaymotors/ws/e...ry=33600&item=7978855718&rd=1&ssPageName=WDVW

Only problem I can see is that it may not push enough CFM.

Kris

 

[63---comet]

I had a 1985 thunderbird that I put a 460 into. For cooling I used a 4 core brass radiator. I tried a pusher fan with no luck. So I went to the local boneyard with my radiator measurements and told them I needed an electric fan, they said "go find the one you want and it's $45" I went to the import section and found an electric shrouded 2 puller fan, I think it was on a Toyota Corrola. It kept the big block at 190 degrees even when idling in traffic in the summer.
So if I were you, I would go look for an electric fan set up from a late model car. There are lots of them in the junkyards and it's cheaper than buying something from Summit or Jegs.

 

[Guest]

Regarding my 62 Falcon...

Finally coughed up the allotted $157 with tax on an off name lifetime warranty radiator. God, they sure didnt design it right, because theres I would say 1/4 or maybe even less even to get the thing in!

I knicked it a slight bit putting it in, but no damage in the functional sense. Back to the 6 fin Ford fan, that seems to have bit more clearance, and rotates more consistently. 1/4 or less, al the way!

I may do an eventual project to bend back where the radiator mounts to in the underhood, for more clearance, especially if the motor shifts and even slightly damages radiator. Im ok with metalwork.

Still mad at myself about the nicks, as you know radiators are like a soft donut, or softer even...dont bump it on anything.

Everything checks out, after a 60 mile round trip, some stopped highway traffic, and heat. Looks great.

 

[cfmustang]

Man am I glad I found yiour post before I replaced my radiator this afternoon.

Remembering what was said here, I test fitted the new 3-row radiator and man was it close to my flex-fan. Lucky, I still had my short spacer and 6 blade put away. I put the short spacer on and volia! a good inch of clearance when there was only maybe 3/8" with the long spacer.

Thanks for the heads up!

 

[Anonymous]

If you haven't started using "Water Wetter" you need to. This product works exactly as advertised. I've been putting a full pint into my radiators and will get you a full 20 degrees or more of cooling as advertised. I can't say enough about the product. I used to have cooling problems in Houston in 100 and even 80 degree weather and it solved all the problems using a good three row radiator and the original fan blade.

 

[Anonymous]

"Water Wetter" you need to.

I ran into someone that says the coolant additive they were using dissolves the radiator hoses from the inside out, I can't remember if it was "water wetter" or some other brand. It turned the rubber into applesauce.

 

[PLP6400]

I was at the L.A. Roadster Show at Pamona, CA this past Saturday and saw an electric fan that will work for our early model Falcons and Mustangs. The Company Rep. told me it was designed for these cars. It is quite pricy at $420.00. The show price was $389.00. It is a 16" puller fan rated at 2,170 CFM. The motor can be placed in any posistion to clear any engine driven accessories.

http://i2.photobucket.com/albums/y17/plp6400/electric-fan.jpg


http://the-fan-man.com/index.php?id=1[/url]

 

[Anonymous]

I would be careful running those flex fans if they are alum. I had one on my 66 Chevy 292 and the blades came apart at higher rpms. Then I replaced it with a stainless steel flex fan.