Thinking of going clutch factory style radiator cooling fan..

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Brooks James

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70 Dart, warmed over 360 magnum, probably about 370 hp

I remember reading here that straight fan sucked about 15 hp, I didn't remember that the hp loss for using a clutch fan was mentioned.

I have a 27 inch plus long x 21 tall aluminum 2 core radiator, biggest one that would fit, it's actually touching the edge of the battery tray

Has a Hi volume water pump

Options
17 inch electric fan, can be either push or pull

Adjustable thermostat

A frig to set up

Or

Clutch fan
No maintenance, nothing to fry and burn, works well, installs in minutes

For now no shroud
Your thoughts
 
Yeah, when I googled 70 Dart factory style clutch fan, many different sizes popped up,I have to do some careful measuring
 
If you get a Jeep wrangler clutch fan they have the shortest shaft that I was able to find. I put one on my 66 with the factory cast iron water pump and shroud. So many said it could not be done…. But I did.
Syleng1
 
If you get a Jeep wrangler clutch fan they have the shortest shaft that I was able to find. I put one on my 66 with the factory cast iron water pump and shroud. So many said it could not be done…. But I did.
Syleng1
Thanks, you saved me
All the research needed.
 
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70 Dart, warmed over 360 magnum, probably about 370 hp

I remember reading here that straight fan sucked about 15 hp, I didn't remember that the hp loss for using a clutch fan was mentioned.

I have a 27 inch plus long x 21 tall aluminum 2 core radiator, biggest one that would fit, it's actually touching the edge of the battery tray

Has a Hi volume water pump

Options
17 inch electric fan, can be either push or pull

Adjustable thermostat

A frig to set up

Or

Clutch fan
No maintenance, nothing to fry and burn, works well, installs in minutes

For now no shroud
Your thoughts

I had a really nice 17 inch electric fan (pulling) along with the thermostatic controller for a few years.
It worked fine with a stocker 318.
When I went to the mild built Magnum it just didn’t cut it.
Swapped it out for an 18 inch clutched type and problem solved.

Pulled it off an 80’s Ford truck and have about an inch from the blades to the radiator.
 
Reminds me of back when many owners were dropping 350s in S10 pickups. here was only one very close clutch available that would work in that application. Very difficult to find too. Rodney @ Adams Auto Parts knew to gather all he could find and got 40 each for them if my memory serves. Of course, that was years ago when close fit electric fans weren't growing on a interweb tree.
If I had to choose today,,, electric fan.
 
I’ve got one of these and it appears to still be too long to fit in my ‘64 Belvedere with a big block so I’m going to get the Jaguar one next.
I have a 64 Polara with a big block and a clutch fan. Been so long since I put it in I don't remember where I got it. Pretty sure it's some kind of Mopar clutch, though.

I did have to melt the solder holding the brackets to the radiator and move the radiator forward, then re-solder. But I think that was because the radiator shop that put a new core in didn't put the brackets back in quite the right spot.

1692375898188.jpeg
 
If you get a Jeep wrangler clutch fan they have the shortest shaft that I was able to find. I put one on my 66 with the factory cast iron water pump and shroud. So many said it could not be done…. But I did.
Syleng1
I have a clutch fan in my 65 Barracuda with the factory cast iron water pump.

1692376013385.jpeg


For a while, I ran a Duster 340 radiator and the later aluminum water pump. Clutch fan wouldn't fit that setup.
 
No one has mentioned that the cast iron pump is 3/4" shorter than the aluminum pump. The respective inlets are on opposite sides also, so his radiator is wrong for a cast iron pump. I may be wrong, but do not think that you will get a clutch fan in there.
 
There are clutch fans that have different degrees of slippage at temp, and "free-wheel" at speed/temp. and don't spin over 4000 rpm, so they don't rob as much power as some would have you believe .
@AJ/FormS has a buncha info, he likes Ford clutches, think they are short, and visibly similar.
 
No one has mentioned that the cast iron pump is 3/4" shorter than the aluminum pump. The respective inlets are on opposite sides also, so his radiator is wrong for a cast iron pump. I may be wrong, but do not think that you will get a clutch fan in there.

Here's an old thread how to shorten an alum pump, to replace the cast pump, to be able to the same rad outlet.
I often just move the rad outlet to the other side.

 
There are clutch fans that have different degrees of slippage at temp, and "free-wheel" at speed/temp. and don't spin over 4000 rpm, so they don't rob as much power as some would have you believe .
@AJ/FormS has a buncha info, he likes Ford clutches, think they are short, and visibly similar.
That's exactly the info I wanted, minimal horsepower drain !!
 
I’ve got one of these and it appears to still be too long to fit in my ‘64 Belvedere with a big block so I’m going to get the Jaguar one next.

The last Jag fan I saw, used a far different "fan" than Mopar .
Lotta folks look, don't measure, only to find they "just" fit, after dozens of posts .
My son's is 1/4 inch away, trans mount is captured, engine won't shift far forward . ( 8 yrs. of spirited driving)
Good luck.

 
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I just dug this out, small block 70 up
A/c pulley for more pump rpm.
Between a 18 inch clutch fan, a ac pulley, hi vol water pump,, and a 27 radiator I think it'll do
Could be too much, I'll have to experiment

Yes it needs reconditioned

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16924771867934922267460971909870.jpg
 
Go Flowkooler water pump if you can, good luck with your parts being compatible!

20220327_144205.jpg
 
, he likes Ford clutches
I only use it because the very first time I encountered one, it was on a new Ford Pick up, 2002 IIRC, and that thing was doing a smoking good job. As I remember it, at lunch time I went straight to the dealer and got one; and 20 years later, it is still working. It is a thermostatic type.
Had it been a Ram on the hoist doing that, I wouldda gone to the Dodge dealer.
I didn't care how big or how small it was, I wouldda made it work even if I had to move the Core support. As it happened, it was a drop in.
My combo:
68 Barracuda, 360 on a 70 Duster340 biscuit mount K, with a Milodon late style Hi-Flo pump, and a rad/shroud/fan/and over-flow tank all pirated off a 73 Swinger 318 A/C auto car. The pulley I just grabbed out of a box of 'em that I had kicking around. Got no idea what it's off except to say that it is bigger than the crank pulley, which is smaller than normal, in an effort to not thro a belt at 7200. So far so good, going on 23 years.
Since 1999, She has run three cams;
the first one was the 292/.508/108 LSA Mopar cam.
Next was a 270/276/110 Hughes cam, and
finally, a 276/286/110 cam also a Hughes.
When I first put her together with KB107 pistons, I had overheating issues that I could not solve. I finally took her down, increased the Bore size a couple of thou, and opened up the top gap factor from .0065 to .0080 and I switched to a Moly 2nd ring from a cast.
And that was the end of running hot. I was so impressed that I began to run her at 205 degrees, and let the fan- clutch do all the work. Badaboom! Goes like a raped ape
This final combo goes 93 in the Eighth. By the calculator this points to 430hp at ~900 ft elevation, and 3457 pounds@ on the start line; and she will, if I ask her to, Idle at 550 all day at 5* advance , she will even pull herself around the parking lot at that, down to 500 rpm/ 3.5 mph, no toe on the clutch.
This is not a brag on my so-called tuning skillz, AFAIK, anybody can make this happen.
BTW, my core opening is still the 6-cylinder size and that 50 year old rad has patches on patches.
BTW, When that 367 is pulling the car around at 500@ 5* timing, I can never hear the Thermostatic clutch kicking in, nor can I feel it. For all I know, it might not even be there. Only the CTS not moving tells the tale. So then, how much power does that 7-blade hi-attack angle, huge A/C, all steel fan, suck out of the crank?
ask me if I care.
 
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