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My 463 never ran hot with 3600CFM dual fans mounted on a Northern Aluminum radiator.
I also installed Dakota Digital fan controller and their relays. SPAL relays failed after 2 years.
That should be fine. I run dual fans on my small block with different on/off temps, and I don't think the secondary fan has ever actually turned on since the primary one is enough. I ground the relay on the second fan as part of my annual routine in the Spring to be sure it still works!
Some say around 10-15hp is freed up with an electric vs mechanical fan. Plus the electric fan is supposedly more efficient at slow speeds as they are pulling max cfm. While a mechanical fan is most efficient at higher RPMs.
It's also nice not to have to worry about having your hand cut off with a mechanical fan running and being under the hood doing work.
With our alternators not rated anywhere near what is out there today, is that ever a concern? Even with ac, I think mine is only 62 amps. Those fans use many amps.
A mechanical fan with a THERMAL clutch takes a minimal amount of power to turn, unless it’s engaged. I have verified this at the track. I made a couple passes, then removed the fan and clutch and made a couple more passes. The car ran exactly the same. If it doesn’t show up on a timeslip, there is no way your “butt-o-meter” will feel anything.
A mechanical fan with a thermal clutch is pretty efficient. Your probably not going to find an electric fan that will move the same amount of air as a mechanical fan, and fit in the same area. Electric fans became common when front wheel drive cane out, there isn’t a easy way for a mechanical fan to fit with the engine turned sideways.
If electric fans were superior to mechanical, then they would be used on heavy duty trucks.
I have Olds powered cars with both. Actually my 70S has the 4 blade non A/C fan and no shroud, two core Copper rad. Actually snuck up to 205 last trip in the city. Wondering whether the drum brakes or this fan or the dying 350 is killing mileage, 17 mpg Imperial with a super lean 307 carb. Should be better with 28" tall tires and a 2004R, 1400 rpm at 60 mph. My 88 Cutlass with electric Pylmouth Breeze fans runs around thermostat temp. Has an A body aluminum plastic rad, makes a big difference. With a 2004R, 26.3" tires and 3.42 gears when that same 307 carb was on it, 20 mpg. The Derale fans are supposed to move a lot of air, should be adequate. My biggest issue is fan controllers with electric fans. All the cheap ones fail in one way or another, add another $150 for something that will last with at least a 60 amp rating. I have the low fan circuit through a 40 amp relay with the key on. The push in sensor was bad out the box, I kid you not, so I clipped the connections into a 30 amp fuse. I have a direct toggle switch for high fans. Go over the reviews and warranty before you buy a controller. Also do a big two core aluminum rad at the same time. Good luck.
Consider the Windstar fans. Got mine for $20 at the junkyard. Ford made A LOT of them, available at every parts store, cheap, work great. Don't forget to upgrade your alternator, wire from alt to starter, and don't try to run them through your existing fuse panel.
Yeah, the Summit chrome 70 amp 10DN alternator has worked great for me. I only had the electric on the 70S for a short time, controller blew the 40 amp relay board almost right away but may go back. The alternator had a 51 amps at idle and 82 amps at cruise performance tag. It is the minimum I would use with electric fans, any less won't keep up.
It's hard to beat a seven blade factory clutch fan with a new Hayden clutch and a good factory shroud that doesn't have any chunks missing.
Finally a 4 core brass radiator or a new aluminum radiator. The car won't overheat if the timing and jetting are correct.
The Dorman 2000 Ford Windstar dual electric fan for $100 seems like a good deal & it supposedly fits in the factory place with very little modifications. Specs shows it pulls 4,500 cfm and each fan pulls around 25 amps.
As far as a controller for it goes, the Davies Craig Digital Thermatic Fan Switch one seems like a good controller. It kicks on the 1st fan at the preset temp and then the 2nd fan kicks on 10 seconds later to prevent overloading the start up amperage on the electrical system. Controller also allows for a manual override so you can run the fans manually. That comes in handy if the car is off and you want to cool down the radiator to prevent heat sink.
Yes, it turns on at the set point, with the start up delay between fans #1 and #2. I think it actually shuts off 5 degrees below temp. Yes, I have the push in probe, very accurate according to my gauge.
I had a couple of overheating events in the 80’s and 90’s. I’m in engine-heat detox now and getting used to my 455’s running 170-180. This winter I changed both cars to a 180F thermostat after at least 25 years on 160F thermostats. I like the change a lot. Seems like gas mileage is up and temperatures are not really up much, except on cool mornings as they should be.
I used to worry a great deal about them going above 180, but am getting over it since the engines run better at 180 or so. But I’ve made a bunch of changes to make things better over the years, so my change in thermostats is at least a decade or 2 late.
I have an A/C big car and non A/C big car. Both use Hayden thermal clutch fans & 7 blade 18” GM fans. Both are shrouded to heck & back on the rear of the radiator using modified ‘66 shrouds (there was only one for A, B & C bodies in ‘66). For both cars, I’ve cut up the driver’s side edge of the factory shroud and added a driver’s side “end” from a ‘67 or 68 toronado shroud to be sure it covers the entire back of the big car radiators. I’ve even put Trimlok rubber bulb seal around the leading edge of the shroud to be sure it seals against the radiator.
Olds cheaped out in ‘66 and the ‘66 shroud only covered about 70% of the big car radiators, but I it probably did a great job on the Cutlasses. I’m aiming at using factory style solutions, but just trying to do it better than they did.
Next, in front of the radiator cores for both cars, I’ve carefully reconstructed the masticated rubber curtains (sides, top, and bottom) that are in effect a “front shroud” and force air to the radiator core and prevent passage of air around the edges of the radiator. I even sealed the top corners to prevent air from leaking around the radiators there.
My mistake was recreating and improving over the factory mechanical solution and then _not_ letting the solution work by retaining the 160F thermostats too long. Once I’d gotten the full shroud, 7 blade fan, and front rubber curtains in, I should have replaced the 160F thermostats with 180F. But I was to overheat scarred (scared?) to do it and kept the cool ‘stats. Turns out that was probably too conservative.
There are a million threads on cooling, they recur every May and disappear in October like clockwork. For those on the electric team with strong new alternators, go for it!. I’m sticking with factory mechanical optimized to about the technology of 1975. Big risk here is when the Hayden clutch fans give up, but that doesn’t worry me much.
Yeah, I also prefer 180 thermostats, 160 is too low and 195 will push temps past 200. Electric fans allow better in town temperatures with 160 thermostat but still run too cold on the highway. Those rubber flaps and the GN air dam on my 88 Cutlass made a massive difference for cooling.
When I swapped over to the 180F thermostats in my street big cars, I also adjusted my water/coolant mix to 70% water/ 30% traditional green glycol. I also added 2 bottles of water wetter. More or less against the views of local experts who advised 50/50.
I went 70/30 since I live near SF and it _never_ freezes here. Per our “authoritative” internet, water has more heat transfer capability than glycol which is there to lubricate and prevent freeezing. I figured 70/30 wouldn’t hurt and might give me some protection from overheating in warm weather traffic. Water wetter / photo flow has worked well for me before, so I continue to use it.
I adjusted the water/coolant mix to aim at Summer cooling since freezing isn’t an issue. I’d always done 50/50, but wanted to see if 70/30 worked better for cooling. A few weeks experience here indicates that 70/30 does cool better than 50/50. Perhaps too much so. Even with the 180F thermostat my engines are running steady at 160F - 165F most of the time.
So now I’m thinking maybe 50/50 with water wetter may be optimal for my driving to keep the temps between 170F and 180F. I’ll take a look at the end of Summer and see how it went.
Decades ago I tried electric fans zip tied through the radiator core. Don’t do this. The early electric aftermarket fans were off balance enough to eventually cause a leak in the radiator core. Modern solutions are undoubtedly much, much better. I’m fine with electric, but I think I’ve gotten where I need to go with a factory style mechanical solution. I’m happy about that.
When I swapped over to the 180F thermostats in my street big cars, I also adjusted my water/coolant mix to 70% water/ 30% traditional green glycol. I also added 2 bottles of water wetter. More or less against the views of local experts who advised 50/50.
I went 70/30 since I live near SF and it _never_ freezes here. Per our “authoritative” internet, water has more heat transfer capability than glycol which is there to lubricate and prevent freeezing. I figured 70/30 wouldn’t hurt and might give me some protection from overheating in warm weather traffic. Water wetter / photo flow has worked well for me before, so I continue to use it.
I adjusted the water/coolant mix to aim at Summer cooling since freezing isn’t an issue. I’d always done 50/50, but wanted to see if 70/30 worked better for cooling. A few weeks experience here indicates that 70/30 does cool better than 50/50. Perhaps too much so. Even with the 180F thermostat my engines are running steady at 160F - 165F most of the time.
So now I’m thinking maybe 50/50 with water wetter may be optimal for my driving to keep the temps between 170F and 180F. I’ll take a look at the end of Summer and see how it went.
Decades ago I tried electric fans zip tied through the radiator core. Don’t do this. The early electric aftermarket fans were off balance enough to eventually cause a leak in the radiator core. Modern solutions are undoubtedly much, much better. I’m fine with electric, but I think I’ve gotten where I need to go with a factory style mechanical solution. I’m happy about that.
If you're running 160 with a 180 thermostat, it's defective. Your temps have absolutely nothing to do with your mix ratio.
A motor will run cooler with straight water, so a 70:30 water to coolant ratio will cool better. The benefit is a raised boiling point and corrosion protection over straight water. Unfortunately here, a 50/50 coolant ratio is necessary at minimum.
I got the Dorman Ford Windstar fan. It comes with one 3 prong and one 2 prong fan connection. Any info on how this wires up using the Davies Craig Digital Thermatic Fan Switch?
I think I figured it out. The 3 pin is just an extra pin for the AC control but it is not used on applications like ours. It's just 2 pins (positive, negative) for each fan.
Will wire each fan to the Davies Control unit and done. Using 8 or 10 gauge wire from fan to Davies relay.
According to specs, each fan uses approximately 22-25 amps.
Those really are great fans. I have them on my 71 with a Champion 2 row rafiator and it stays dead nuts on the 180 t-stat no matter the conditions. I have the 2nd fan set to come on at 205 and I am guessing it works but has never triggered in the 4 or so years I have driven the setup.
I was thinking of using JB Weld to epoxy a bolt onto the radiator and using it as a mounting stud on the solid part of the radiator. Then using the mounting stud on the fan to run a nut/washer to tighten it down to the radiator.
The windstar fans have 4 mounting pads on the outside. Make some brackets out of flat stock and bend them to fit so you can mount the fans to the radiator support. As far as the lower hose you will need to cut the shroud around the hose outlet a little. Pretty minor fabrication but easily doable without many tools.
