What's considered best setup for HD cooling?

As far as fan setup, keeping everything Mopar. Seven blade factory fan, direct drive or clutch fan?

Thank you.

the direct drive vs clutch is where I will throw my 2 cents.

If I were looking between those I would pick direct drive.
might rob a few hp at the top, but is simpler and less to go wrong.

if that clutch goes out the wobble will kill your wp bearing and then eventually eat a rad.

If you can drive your car long enough for a wobbly fan clutch to wear out a WP bearing and eat a rad you have a numb butt.

The factory put millions of clutch fans on all sorts of vehicles and they worked just fine.

I like the M body setup if it's not too long to fit.

Ok. I have a 7 blade clutch fan on my M body and have for years. I understand where you are coming from Andrewh but I think I'm in touch of enough with my car to notice if the clutch is going out. I'm replacing the rad in in Power Wagon and I'm going to replace the crappy fan and clutch at same time while everything is out. Time to head over to online swap-meet to see if I can find a fan for sale. Thank you.

add an anticav plate to the pump (easy welding job). the most fan blades (you're set there). hi flow stat (180 or higher). overdriven pump. fan blades spaced properly into the shroud. spring in lower hose. good/adequate radiator.

Already have the Milodon anticav pump and a milodon stat. Couldn't find a hose with spring anymore. I think they are all gone but I think I'm ok without. I'm down to the fan now. Radiator is on order. Thanks Robert.

New radiator came today and I ordered wrong one. I didn't realize my Power Wagon had HD Cooling. So back goes the one I ordered and I ordered correct one today. But I see I have fixed five blade fan fan with spacer, and everything looks stock. This is one my Power Wagon, btw.

I like and run a thermal clutch fan. The kind with the little thermostat coil in front of the clutch.

Yes it saves some HP. Also it saves the ears when cruising... a fixed fan can make a noticeable roar. Also it acts as a speed governor for the fan... safe in my experience and others for a ~6,500 RPM redline.

My current fan is a Bouchillon 6 blade with their thermal clutch offering. Works quite well on a warm 496 w. AC. A factory 7 blade with matching clutch should be fine also. Other parts of the package include a HV water pump with anti-cav plate, slightly overdriven fan and water pump and a high capacity 26" aluminum "Muscle Car" radiator from Mancini with matching shroud.

If you will always keep the car in a heated garage and don't drive in the winter, the best coolant is pure distilled water with no antifreeze. Use Water Wetter for corrosion resistance and surface tension reduction. Water has the highest specific heat of any material. Adding stuff to it reduces cooling capacity. I am successfully cooling a stock 426 Hemi with a 22 inch brass radiator this way.

ahy, I already have a Milodon HV pump with anti-cav plate, and I've already ordered a Spectra radiator. Not crazy about the aftermarket radiators, but want to get truck on the road now. I'm taking the factory original HD cooling radiator to a rad shop and having it re-cored sometime in near future when I have the money. It will be on standby storage for when the Spectra fails, and go back in the truck. DougR, I have distilled water with a mix of coolant in all my vehicles. I've never run just distilled because I do some occasional Winter driving, albeit just in Florida, it can drop below freezing. Thanks for advice though.

I appreciate the advice and I'm cruising ebay now for a stock Mopar 7 blade clutch fan over the Bouchillon to save a few dollars, plus I like the stock Mopar look, and I'll probably buy a new clutch.

Thanks all for good advice.

p.s. I ran out of paint when it came to the Milodon pump but I'm going to get to it soon. Also, just had to bypass heater because the core started leaking right on time for Winter. Looking for a NOS core or I'll have that re-cored too. Done with aftermarket junk whenever possible.

Doug does water wetter have enough rust/corrosion additives to prevent that? Larry are you going to paint that pump blue!

Sounds like a good setup. I do not know the Spectra radiator... though you may be fine. I run a Champion radiator on a PU and it works well. I would suggest good antifreeze to protect the system... I like and run Prestone extended life. My aluminum radiators have held up very well with this coolant.

I have the original 26" rad in my 70 sport satellite, had it recored with high efficiency core, factory shroud, a/c water pump (car has/is a/c), factory 195 deg stat... . 7 blade fan with thermostatic clutch . . . all I can say is, DAMN, this thing runs way cool !!! . . . on the temp gauge, it is on the second line up from the "C" . . . not even half way on the gauge. Everything is/was new when put together .. . . 10k miles on it now !!!

So back a little while, and I had the car running hot when you got over 60mph. Around town, no problem . . . also there was a noise like valve train noise, and a "vibration" in the steering wheel (only) . . . after 5 years, finally figure out I was missing a triangular piece that goes between the power steering pump bracket and water pump. Without the triangular bracket, the power steering pump was vibrating and broke the mounting bracket, making the noise and vibration !!! . . . also, because on small block ac car, the water pump and power steering pump are same belt, it was "loose" . . . all problems gone with correct brackets (yes replaced cracked/broken ones and added the missing one) . . . car is quiet at speed now, no vibration in steering wheel and runs totally cool !!

Sorry for the hijack . . . hope this might help someone else . . .

Cheers,

Mark

Jam the biggest radiator you can in there. That does the trick. Some worry about the opening needing to be cut. I don’t worry about that. 26 where a 22 grew is fine.

Yes. I was so pi**ed, I ran out of paint, but made sure I got all the tough to reach spots very thoroughly. Local parts store did not have any more. I'm going to pull brackets and sand and repaint them black and hit the pump. I ordered another can of the Mopar paint.

Generally speaking, a direct drive fan is limited to fan blade size/pitch because of the power needed to drive it. (belt slip) A clutch fan can have a much more aggressive blade profile and will move more air at the rpm it's needed.

I'm about to buy a fan/clutch. Should my goal be to get largest (18" or 20") that will fit within shroud? Also, should I space it as close to radiator as safely possible, i.e. the closer to rad the better for cooling?

Thanks,

Larry

(1) largest dia but with some circumferential clearance (2) You want the fan ~1/2 way into the shroud

Ok thanks Robert.

Thanks for all the advice, and this is on the way to me. I'll sand and paint, and install with my factory re-cored radiator.