Electric fan or not ?
The mechanical fan can have it’s blades at a higher angle of attack and have much longer chords on each fan blade to Move LOTS of air. After all it’s being turned by the water pump who’s only limit is the belt(s) driving it.
An electric fan is going to be more limited in this regard, by size and amperage available, at least when you limit the diameter to one that will fit in your current shroud.
it would work I suppose but move less air. Without A/C and if it wasn’t too hot or humid outside it would probably keep up fine.
You just need a good wiring/relay setup and good voltage.
Plus no more fighting with the satanic fan shroud and great wheel of death when working under the hood.
A Lincoln MKVIII fan is a 17” single, and MORE then enough to keep anything cool. My fan cycles on and off with a temp switch and/or the AC compressor and my car never goes over 190* in the middle of Summer 95-100* and humid. My car can literally idle for hours with the AC on and never go over that temp. Usually it stays at 185* ish with it cycling. I have a manual override switch and I can force the fan to stay on and it will cool into the upper 170s on a 95* day. This thing cools 10x better then the stock 7 blade clutch fan and Severe duty clutch at idle/low speeds.
You just need a good wiring/relay setup and good voltage.
Plus no more fighting with the satanic fan shroud and great wheel of death when working under the hood.
But where did you get the shroud?
Jebby
Last edited by Jebbysan; Mar 14, 2019 at 01:34 PM.
the efficiency of the fan is dependent on the associated shroud as well, and how far from the radiator that shroud is mounted. so a mark 8 without it’s associated shroud or mounted farther away may not work as well.
not saying it won’t work, just potential issues that may arise. If a guy can get his hands on a mark 8 and likes to experiment, I say it’s worth a try.
The level of fan noise was downright embarrassing for an "exotic" car. "Hey buddy I think you left your motor on!"
I went from having a puking problem to a flat battery problem rather rapidly.
The solution was to FIX the actual cause of the overheating, not to install a bigger fan.
Endless pressure leaks were one cause of the E-types chronic overheating, but the biggest was the incorrect thermostat in mine and just about every other XKE still on the road. The original t-stat from Jaguar/ British Leyland, and no longer available, was a dual-disk design that not only opened up flow to the radiator, but closed off flow to the bypass line using a second disk.
That t-stat wasn't available anymore and almost every XKE out there had the identical overheating problem because the SINGLE DISK replacement t-stats available left the 1" bypass wide open even when the engine was hot. They'd recirculate hot coolant instead of pumping it through the radiator since that was a longer path that demanded more pressure than just taking the bypass.
Compounding the problem was the LACK of an Internet with which to spread this "bypass" information to others.
Once the problem was fixed (for me, with a massive bolt, nut and washer plugging the bypass line) the car got by with little to no fan at all. Oh I'd flip it on stuck in traffic now and then, but it never headed for the red like the good old days. No more puking after shutdown.(That correct original thermostat is NOW being reproduced by somebody.. according to a Jaguar guy in Scottsdale I chatted with)
Likewise, with a new radiator, t-stat, leaks all fixed... my Vette (350, mechanical fan) will idle in the driveway seemingly forever before reaching t-stat opening temperature.
You don't need a massive fan. A medium fan will do, even on an AC car, provided EVERYTHING ELSE in the cooling system is working properly.
Pressure test the cooling system, correct 50/50 coolant, new radiator cap, proper burping.... cover the basics. Correct timing & mixture. Oh and make sure all the fan shrouds and foam pieces are in place so the air actually goes where it's supposed to.
Not massive fans.
Last edited by wadenelson; Mar 14, 2019 at 05:58 PM.
But where did you get the shroud?
Jebby
A real MKVIII fan has the shroud built onto it. It’s all one unit. The pic above is a real Lincoln MKVIII fan. They are usually around $150 on eBay, they are 1 speed (though many claim they are 2 spd). You need a good 50 amp relay and 8 ga wiring for it.
Last edited by htown81vette; Mar 14, 2019 at 02:00 PM.
The level of fan noise was downright embarrassing for an "exotic" car. "Hey buddy I think you left your motor on!"
I also went from having an overheating problem to a flat battery problem rather rapidly.
The solution was to FIX the actual cause of the overheating.
Endless pressure leaks were one cause of the E-types overheating, but the biggest was the incorrect thermostat in mine and just about every other XKE on the road. The original, from Jaguar/ British Leyland, and no longer available, was a dual-disk design that not only opened up flow to the radiator, but closed off flow to the bypass using the second disk. That t-stat wasn't available anymore and almost every XKE out there had the same problem because the replacement t-stats available left the 1" bypass wide open even when the engine was hot. They'd recirculate most of the hot coolant instead of pumping it through the radiator.
Compounding the problem was the LACK of an Internet with which to spread this valuable information to others. I did write it up for a Jaguar newsletter back in the day.
Once the problem was fixed (for me, with a massive bolt, nut and washer plugging the bypass line) the car got by with little to no fan at all. Oh I'd flip it on stuck in traffic now and then, but it never headed for the red like the good old days. (That correct original thermostat is NOW available again, being reproduced by somebody.. according to a Jaguar guy in Scottsdale I talked to)
Likewise, with a new radiator, t-stat, leaks all fixed... my Vette (350, mechanical fan) will idle in the driveway seemingly forever before reaching t-stat opening temperature.
You don't need a massive fan. A medium fan will do, even on an AC car, provided EVERYTHING ELSE in the cooling system is working properly.
Pressure test the cooling system, correct 50/50 coolant, new radiator cap, proper burping.... cover the basics.
Not massive fans.
Seriously... think about it... I run a single brushless fan on a 650hp 427 SBC on the track at over 100* pushing 4-7K RPM hard for over and hour... come into the pits... no problems with over heating at all..
Last edited by pauldana; Mar 14, 2019 at 02:02 PM.
The Best of Corvette for Corvette Enthusiasts
But I will add a proper tune is important as well.Jebby
That link you posted is not a real Lincoln MKVIII fan... it’s click bate in the title.
A real MKVIII fan has the shroud built onto it. It’s all one unit. The pic above is a real Lincoln MKVIII fan. They are usually around $150 on eBay, they are 1 speed (though many claim they are 2 spd). You need a good 50 amp relay and 8 ga wiring for it.
BTW....it very well may be "two speed" but not by the fan itself.....my 98 Mustang GT had a two speed fan controller in the fender....SOB quit going on high speed too and my car would overheat in traffic all of the time......drove me crazy because the fan IS working...just not enough....took about half day on the internet to figure that one out.
Jebby
Start by pressure testing your cooling system. That needle SHOULD NOT MOVE AT ALL for at least 30 minutes after you pump it up.
No insult, but a 160 thermostat is typically a sign that a DIYer couldn't properly diagnose cooling system problems.
yes, there is 2 power wires to the motor, the speeds were controlled by relays and/or pulse width modulation from the PCM on the later years. However, if you hook 12v to either wire, it will run the same speed. You could certainly add a controller to ramp in the voltage or limit fan speed by temp but.... I don’t. I just run it on high anything it’s triggered to come on. I literally never know it’s running inside the car.
Surprisingly, the fan is not loud, especially over a hot rod motor and exhaust. My wife’s 16’ SS Camaro with the Brushless fans sounds like a vacuum cleaner running under the hood in comparison
On the Hot Rod Power Tour in 2017, some of the lines at the venues took us over an hour to get into, idling with the AC on the whole time in 90*+ temps. Never went over 190*.
The Lincoln fan in the last pic is about to go on my dad’s 70’ Nova SS 350 that refuses to stay under 220* with the AC on with a 7 blade clutch fan and Hayden severe duty clutch.
Start by pressure testing your cooling system. That needle SHOULD NOT MOVE AT ALL for at least 30 minutes after you pump it up.
No insult, but a 160 thermostat is typically a sign that a DIYer couldn't properly diagnose cooling system problems.
Last edited by htown81vette; Mar 14, 2019 at 04:03 PM.
Some of the best money I ever spent on my two SBC S10 Blazers was to remove the mechanical fans and replace them with junkyard early 90s Taurus fans. I used cheap ~$15 fan controllers (from Oreilly's or Autozone), 40A relays, 8 gauge wire and wire loom to make it look nice. I only had about $60 in each setup and they kept those 10:1 iron headed small blocks cool. Usually around 165° but never saw more than 190° even in 100°+ temps.
I had a spare fan for each truck too. Picked those up on a holiday weekend at pull-a-part for $15 each.
The axial fan impeller uses airfoil design that have a round leading edge, a sharp trailing edge, and in profile or cross section, look similar to a teardrop that has been flattened on one side. As air approaches the blade’s leading edge, the stream splits and travels above and below the blade. Air is deflected across the convex curve along the top of the blade and along the flat or concave curve on the bottom of the blade, and flows downward over the sharp trailing edge as it leaves the blade. According to Bernoulli’s Principle, faster moving air across the top of the blade creates less pressure than the slower moving air on the bottom of the blade. This creates lift in an airplane wing or airflow in an impeller. Airfoil impellers function just like a series of small airplane wings attached to a hub, with one notable exception. In axial fans, the airfoil’s twisted design ensures that the incident angle between the airfoil and the airflow is constant along the blade length, giving a uniform blade loading for high efficiency, low noise fans.The airflow of an axial-flow fan should be evenly distributed over the working face of the fan wheel for improved efficiency. This means that the axial air velocity should be the same from hub to tip. The velocity of the rotating blades are not evenly distributed as you move out from the hub. The speed of the blade is low near the center and increases toward the tip. To even the airflow, this should be compensated by a twist in the blade, resulting in larger blade angles near the center hub and smaller blade angles toward the tip. At high static pressures, the blade twist is important, because without it, the inner portion of the blade will stall and permit reversed airflow, which, will seriously reduce the fan efficiency.Computational Fluid Dynamics (CFD) techniques can provide the fan design. The simulation results give the pressure drop across the fan, velocity contours over the fan blades, and path lines of air as it flows past the fan. It also shows the pressure contours and wall shear stress contours on the blade surface, helping to understand which regions face high pressure and which regions face high shear. CFD results can also provide valuable information that will help optimize the design. Changing the geometries of the blades and several iterations using CFD analysis, an optimal design is reached that improves efficiency using:
- Flow uniformity
- Evenly distributed pressure from hub to tip to prevent reverse flow (see figure 5)
- Locations of potential cavitations and noise generation
- Fan performance curves
Last edited by pauldana; Mar 14, 2019 at 05:25 PM.
Part number is on shroud.
Lot's more info here than you'll ever need:
1998 Mark VIII fan, part numbers RF-64 and/or F8LH-8C607-AA
https://www.corvetteforum.com/forums...post1559765076
Last edited by carriljc; Mar 14, 2019 at 07:34 PM.















