Clutch fan recommendation needed

I'm trying to choose a clutch fan for my 69 Dart and have several options available. Just got the engine in the car so it hasn't been driven yet. My engine is a 400/470 with 10.8 cr, Eddy heads, 727 and 3.73 gears. My radiator is a 3 core 22" factory radiator. I have a 195 degree thermostat installed. I have 3 fans with clutches to choose from. One is a factory 7 blade and clutch from a 67 GTX. The second is a factory 7 blade with aftermarket clutch (not sure of brand) from a 72 340 Duster and the third is the Mopar Performance 5 blade fan/clutch package. Which would you think would provide the best cooling?

Have you tried to put any of them in there? The spacer used with a fixed fan is only 5/8" thick on a BB A body , if your engine and radiator are in factory locations there is not a lot of room. I imagine the factory would have put in a clutch fan if there was room ?

I tried test fitting all of them and they all fit fine. Just trying to decide between the 5 blade and the 7 blade.

Go with the 7 blade, just make sure the blades are 1/2 way in the shroud.

Most clutch fans available today for Mopar are too tall if U have installed bigger radiator...
I have a couple of short height(2.75") mopars with the closed WP hub if U require one.
Just send me a PM if any further interest...

Just my $0.02...

Thanks, I appreciate it. I will recheck everything again to see how far the fan blades go into the shroud as well as how much distance is between the fan blade and radiator fins. The radiator is a 22" 3 core from a 72 Duster or Dart as is the shroud..

Hayden do a short HD muscle car fan clutch . Stronger drive (less slip ?) than short Jag unit some use . I use this HD unit with Mopar 5 blade on my Satellite . I do use a manual control smallish electric fan on the front of radiator for the really hot days and heavy traffic .

Tex

After taking some time away from it, I'm finally working on finishing up my engine cooling. Turns out with the radiator I ended up using that I am going to need a shorter fan clutch. The clutch I have is about 3 5/8" in depth. With it, the seven blade fan I am going to use sits all the way into the shroud to where the back edge of the blades are flush with the shroud opening. So, it looks like I will need a clutch less than three inches in depth to get the fan blade half in and half out of the shroud. Who sells clutches that are less than three inches in depth?




I tried messaging you Sinitro but was unable to.

hayden fan clutch If this is fairly cheap I may have to look into this , The fixed 7 blade I'm stuck with on my dart is a HP robbing POS

bought mine @ Rockauto . Priced ok .

Tex

I use a Hayden Jag clutch with 7 blade fan. I use a 160* T Stat. Engine hardly ever reaches 160*. All fan clutches engage at around 180*. The degree of engagement is different from standard and heavy duty. If I recall, standard duty is about 60% engagement, while heavy duty is around 87% engagement

I found it on rock auto , 49 and change but once you add in shipping it gets close to the amazon price of 59 with free shipping , still cheaper than summit at 69.99 plus the ride

How much space do you have between the pulley face and the radiator , my car is apart so I can't measure it .

What application is the Jag clutch for ?

1990 XJ6

4 1/8"

Thanks , that hayden one should fit , I wonder if putting a thin spacer between it and the fan blade to move the blade back some , if it needs it , would cause a problem ?

Thanks , rockauto here I come

I see that is the Hayden 2765 unit. I was reading a thread over on FABO where the Hayden 2947 unit was recommended. Does anyone have any experience as to which one is the better choice? They look pretty similar but the 2947 has a little large mount diameter.

Good question , according to the specs on rockauto , the 2765 is about .050 shorter than the 2947 .

2947 is the HD shorty. other is standard duty.

Sorry never received any PM.
Note I did post an ad in B Body Parts for a short height (2.75") clutch fan...


Just my $0.02..

You didn't receive it because I couldn't send it. When I tried, I got a message saying "This user is not accepting Private Messages".

As I stated previously, other than the.050” difference, the percentage of lock up is the only difference between the two HD will lock up tighter and cause a slight loss of horsepower. I would suggest the standard duty clutch and a 7 blade fan. More blades, better cooling.
Just my 2 cents.

No idea what happened..
Just double-checked and the Accepting Private Messages option is turned on.

Just my $0.02...

Just tried again and now it works.

I didn't realize that HP loss locked tighter , standard duty it is with a 5 blade fan

I found this while trying to decide between the 2765 and the 2947.

http://www.dodgecharger.com/forum/index.php?topic=129049.0

2017 , is that the only failure you've found ?

It's the only one I came across. I wasn't looking for failures, just came across it when searching for comparisons between the 2765 and the 2947. I didn't know that a failure like that could even happen.

So, if I understand this correctly, the 2947 clutch would cool better in city driving due to the higher percentage of engagement? I'm not concerned with hp loss as much as cooling efficiency. Also, I am uncertain about the number of blades on the fan. From what I've read here and elsewhere, some say the 5 blade is best while other say the 7 blade is better. I'm uncertain which combo to go with, 2965 or 2947 clutch with 5 or 7 blade fan.

This is correct, the HD clutch will cool better in traffic. The 7 blade will pull more air than the 5 blade. Example, if you look at a helicopter that is made to lift heavy loads, it has more blade than one that is not made to do so. Another example, look at OTR trucks. None that I’ve seen have less than 6 blades. Even newer passenger trucks have more than 5 blades.

This is a great subject, that came up at a good time, as I have been thinking about fans on my Factory Appearing build. I have a big block A body and standard its equipped with a 7 blade fixed fan with a 5/8" spacer , hoping that one of these short clutches fits and put the fan in a good spot within the shroud, otherwise a fixed 4 blade fan might be finding a home in it for racing.

Been doing a lot of reading up on these clutches and the fans as well John. Right now, I'm leaning toward the 2947 clutch with a 7 blade fan unless someone convinces me that a different combo would be better. As I mentioned, I'm more concerned with cooling efficiency rather than hp loss.

I use the Mopar Performance 5 blade works good for me . With an AFCO aluminium cross flow radiator and factory shroud .

Tex

I tried the MP 5 blade assembly a while back. Nice and quiet, lite, but didn't pull much air and hence, I had trouble keeping the engine cool. I believe it would be a good choice for a race only application. Not so much in a street/strip car. Again, just my 2 cents.