Clutch fan options on my 340?

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Hey its only time, figured id ask, i know sometimes things can get too complicated, its just weird that hayden makes a HD clutch but doesnt have a fan they reccomend to use with them, i may have to contact them.
 
The MP books recommend there “Viscous fan” set up. 5 blades, not symmetrical.
 
Ok so weather it be a 5 or 7 blade clutch fan i should be good running a factory blade with the hayden 2947 right?
 
OMG!

Do whatever you want, run an electric fan......
 
72Dart6pack said:
This is the exact part you need. 340 clutch fan set up. No it's not for sale. Just a picture so you know what you are looking for.

View attachment 1715113817
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Actually,it's not. The MP viscous fan package has been proven to move more air than any other Mopar clutch type, or solid fan. Period. What you have pictured is not it.
 
Why is there always a issue, either there is a miscommunication or im not getting the premise on the correct setup. One thread shows the 70-71 dodge part list and under dart shows the 340 to have a 7 blade, then you state a 5 blade is reccomended, im just trying to learn the difference between the two and what is the best option for both availability and functionality with a fan clutch, i have no problem running the fixed fan but i figure if i can free up 10 hp or more it would be worth the time spent trying to learn about the setups with fan and clutch lol
 
RustyRatRod said:
Actually,it's not. The MP viscous fan package has been proven to move more air than any other Mopar clutch type, or solid fan. Period. What you have pictured is not it.
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You’d think that everybody would have read the MP speed secrets book.
 
Thank you rusty, thats what i wasnt understanding, now that i have a picture to look at i completely understand now, why is there so many combos available? It seems like a lot of confusion especially for someone whos not expirienced in clutch fans as much as yall
 
Sorry rumble, wasnt even aware of it, thats why i wasnt getting when you said MP viscous fan setup i honestly had no clue what MP was
 
71DodgeDemon340 said:
Thank you rusty, thats what i wasnt understanding, now that i have a picture to look at i completely understand now, why is there so many combos available? It seems like a lot of confusion especially for someone whos not expirienced in clutch fans as much as yall
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Yes and you’re welcome to.
72Dart6pack said:
I'm leaving this post. Good luck on your quest!
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Make sure you stop by an online source can purchase the engines book where you can find out the information you keep asking for that’s only been up for like the 50 years Rusty said.
Or is a book to Barbaric for you?
 
71DodgeDemon340 said:
Thank you rusty, thats what i wasnt understanding, now that i have a picture to look at i completely understand now, why is there so many combos available? It seems like a lot of confusion especially for someone whos not expirienced in clutch fans as much as yall
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The MP fan I linked to is the Mopar Performance version. The other version shown earlier in the thread is a standard stock unit. The 5 blade fan moves more air because of the asymmetrical five blade design. Mopar put a lot of R&D into it and that's what they found. It also comes with a thermostatic clutch, which as already described to you, gets closer to lockup, the hotter temperatures get, in order to move the fan even more. They move a LOT of air. But as I stated, make sure you use a fan shroud.
 
Yeah i want blue prints for a proper size fan shroud lol and the accetable tolerances between the fan and shroud and fan and radiator.

I always have and always will run a shroud

Ok so it looks as though the MP viscous fan setup is almost non existent. Classic industries says available soon but who knows when that will be. So i guess theres no sense doing anything other than the MP setup right? I just dont trust the other options for clutch fans as hayden cant even reccomend a fan for their HD 2947 clutch which from other threads on here had pretty much been made for mopars. But no fan to match up to it.

However if i could find a used MP 5 blade i could use the hayden clutch anyway and it would be more or less the same setup
 
71DodgeDemon340 said:
Yeah i want blue prints for a proper size fan shroud lol and the accetable tolerances between the fan and shroud and fan and radiator.

I always have and always will run a shroud

Ok so it looks as though the MP viscous fan setup is almost non existent. Classic industries says available soon but who knows when that will be. So i guess theres no sense doing anything other than the MP setup right? I just dont trust the other options for clutch fans as hayden cant even reccomend a fan for their HD 2947 clutch which from other threads on here had pretty much been made for mopars. But no fan to match up to it.

However if i could find a used MP 5 blade i could use the hayden clutch anyway and it would be more or less the same setup
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This is it. They were stock in the 80s on police Diplomats. You can get a new clutch from pretty much any big box store. Just get one for like an 88 Diplomat.

Mopar Viscous 5 -Blade Clutch Fan OEM Factory 18 Inch Dodge 318 Truck Cars | eBay
 
Ok looked up 88 diplomat clutches on oreillys. They list the 2747 clutch and the 2947 clutch which is the supposed improved design. Interesting
 
71DodgeDemon340 said:
Ok looked up 88 diplomat clutches on oreillys. They list the 2747 clutch and the 2947 clutch which is the supposed improved design. Interesting
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IMO, the five blade is far superior to the six. I think what's happened is, rather than make more than one part, they superseded to the six blade, but that doesn't make the six blade better. It simply makes it cheaper for THEM since they are now only producing one fan.
 
Thanks all. I appreciate the clerification on clutch fans, so ultimately i need to buy the five blade fan and clutch setup in the link rusty gave me and replace the clutch. Also how do these things hold up to high rpm? Ive never seen 5500 in my demon but the cams good till 6200, havent had a problem with the fixed fan and im sure any factory chrysler fan will hold up to it but im a little leary on the fan clutch at higher rpm, maybe im just too cautious but i deff dont want to replace a 300-400 dollar radiator.

I also have a question in general about the fan blades. Are the pitch of the blades the same between the 7,6 and 5? Or is the less number of blades the greater the pitch?
 
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Just did a quick measurement. Im running a one inch spacer with my fan now. Fan is pretty much centered with the fan shroud, half in half out. The 2947 is 1.09 inches from flange to where the fan mounts, so assuming the 5 blade fan is the same exact as the 6 i should retain proper fan placement. Also the unit is just shy of 2 3/4” overall length and should put the front of the clutch right at a inch away from the radiator. Sounds like a perfect setup right?
 
Just bought the 5 blade setup on ebay, thanks again rusty for the link, as long as the 5 blade is the same offset as my current 6 blade i should be good to go. Going to hold off on the new clutch for now until i get the fitment of the 5 blade fan confirmed, if its spaced the same in the shroud as my current 6 blade then i will order a new clutch
 
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