Elec. Fan: How Much Cfm Is Enough To Keep My 363 Cool?

95Vert383AOD said:

I have a topic related question....

I was running the 97/98 Mark 7 fan for a while in my 95. I was using it as a single speed fan. Didn't really have an issue. for a couple of years. Just wondering if anyone knows if someone would need a BEEFED up CCRM. (For cars using a CCRM)

My CCRM failed and i wasn't sure if it was the draw of the fan or the fact that it was so old it looked like it came off the Titanic. I got a good 2 years with the old CCRM.

I know its not 5.0 Related because you guys don't have them.... But since Amperage is so high a strong relay is needed. I read on some other forums about fires resulting from 40amp Relays melting.

Chris

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Chris, that is why IMO you need a VSC that has a soft startup feature like the DCC or Flex a lite 33054 controller. You won't get the huge amp spike and keep risk frying wires or your fan not working. IMO your cooling system is extremely important and it is worth the $100 to make sure the fan is operating properly.

It would be awesome if it could operate in a manner that retained the variable speed. Is this technology pure Ford Voodoo or has someone figured out how to make a variable controller?

I've posted the answer twice. Buy one of these and your problem is solved.

http://www.summitracing.com/parts/FLX-33054/

or

http://www.dccontrol.com/relay_controllers.htm

Link 1 is only 45 Amps. I'm not comfortable when the fan has a constant draw of 30-40 amps. An aging fan with a bad bearing would melt that.

Link 2 is 2 speed.

Mark VIII fans are variable speed. So decreasing voltage should in effect slow the fan.

They say on the Mark fans there is a Ground and the other 2 leads are tied together. Some fans are even missing the middle lead on the harness.

Here's my Idea.... Run the high speed circuit as normal but put some kind of resistor or regulator on the low speed to cut the voltage down to maybe 7-9 volts. This way it would make the fan 2 speed.

Whatcha think??

95Vert383AOD said:

Link 1 is only 45 Amps. I'm not comfortable when the fan has a constant draw of 30-40 amps. An aging fan with a bad bearing would melt that.

Link 2 is 2 speed.

Mark VIII fans are variable speed. So decreasing voltage should in effect slow the fan.

They say on the Mark fans there is a Ground and the other 2 leads are tied together. Some fans are even missing the middle lead on the harness.

Here's my Idea.... Run the high speed circuit as normal but put some kind of resistor or regulator on the low speed to cut the voltage down to maybe 7-9 volts. This way it would make the fan 2 speed.

Whatcha think??

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If you don't have a high current alternator, you can forget about using an electric fan. The stock 65 amp alternator on 86-93 Mustangs isn't big enough to run the fan and the rest of the car. If you have a 94 or later Mustang, the stock 3g alternator should be fine if it is working correctly.

The resistor idea will not work. You will not be able to find a suitable resistor with the correct resistance and wattage to effectively do the job.

Here's how varible speed fan controllers work:


Switching a fan on and off manually is a bad idea. Too many guys have been distracted (hot girl kissing on their neck, too much to drink, dog tired and not thinking clearly) and cooked things because they forgot to flip the switch. An equal number have forgotten to turn the switch off for the same reasons and run down their battery.

The best fan controller available today is a DC Control unit. www.dccontrol.com. Cost is about $???. Be prepared to wait 4 weeks or more to receive your controller once you have sent in your payment. The controllers are custom made in small lots and lead times can stretch out.

Next best is a SPAL controller - $70-$120 See http://www.spalusa.com/store/Main.aspx?html=pwmv3. eBay will have the controllers for a bargain price: do a Google search and see what you find.

At the bottom are the Hayden or Imperial controllers available through Advance Discount Auto Parts and AutoZone. The non adjustable one is about $30 ( Hayden 226206) and the adjustable one is about $60 (Hayden 226204). I recommend you do a Google search on Hayden and the part number for more info.

Do not use a simple on/off switch without using a relay. The current load can burn up the typical cheap automotive switch very quickly. The fan draws 30+amps and you need to use #10 wire on the fan power and ground wiring.

If you are good with electrical stuff (90% of the people here aren't), build your own controller. The numbers on the diagram (#86, #87, etc) refer to the numbers on the bottom of a typical automotive relay.



Note that the temp sensor in the diagram needs to match the thermostat in your engine. The preferred arrangement is to have it open about 5 degrees above the thermostat.

To allow the ignition switch to control the fan so that it does not run when the ignition is off, connect the relay contact #86 to the red/green wire on the ignition coil or to the red/yellow wire on the coolant level sensor.

If you are an experienced electronics tech or electrical engineer, email me and I will send you the prototype drawings of a fan controller that is similar in function to the DC Control unit. It is a build it, troubleshoot it yourself item. I will not build or troubleshoot units, so it is not suitable for anyone who isn't really good with electronics.

Alternate placement for a temp gauge sender or temp switch/temp sensor for an electric fan. Use the heater feed that comes off the intake manifold. Cut the rubber hose that connects the manifold water feed to the heater and splice in a tee adapter for the temp gauge sender. Be sure to use the same water feed line as the ECT sensor. That way you will get the most accurate temp readings.

Tee adapter info:
Make a pilgrimage to your local hardware or home supply center and get some copper pipe and a tee that fits the temp gauge sender. Solder two pieces of copper pipe onto a copper pipe tee with threads in the tee part. Find the correct brass fitting to match the temp sender threads to the tee fitting.

Exile said:

This is a Ford Taurus fan that I picked up (free) mounted on a stock radiator. (for now) Monster can "overflow tank" lol
Im waiting to get the rest of my parts to complete my h/c/i setup, then the fan will be mounted on my Griffin aluminum radiator.





I live in Texas, and it always stays nice, and cool!

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I have been running a Taurus electric fan for a while now using the stock 91' Mustang alternator, and have had no problems. (yet)

Exile said:

I have been running a Taurus electric fan for a while now using the stock 91' Mustang alternator, and have had no problems. (yet)

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Here's the math, so see for yourself...
Electric fan = 3G alternator if you want long life & reliability from your car.
The electric fan saves some HP. The stock fan's parasitic drag runs from 7-12 HP depending on who you talk to. The electric fan uses about 1/2 HP of power from the electrical system.

Figure this:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
Fan (heater or A/C) = 15 amps (can run between 5-25 amps depending on setting)
Radio & instruments = 10 amps
Wipers = 10 amps

That's grand total of 74 amps from a 65 amp alternator. Talk about overdrawn at the bank!

jrichker said:

Here's the math, so see for yourself...
Electric fan = 3G alternator if you want long life & reliability from your car.
The electric fan saves some HP. The stock fan's parasitic drag runs from 7-12 HP depending on who you talk to. The electric fan uses about 1/2 HP of power from the electrical system.

Figure this:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
Fan (heater or A/C) = 15 amps (can run between 5-25 amps depending on setting)
Radio & instruments = 10 amps
Wipers = 10 amps

That's grand total of 74 amps from a 65 amp alternator. Talk about overdrawn at the bank!

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My Car/Figures:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
No Fan (heater or A/C) = - 15 amps
No Radio = - 10 amps
Wipers = 10 amps

Grand Total of 49 amps from my 65 amp alternator.

But I know what your saying, and a 3G alternator is in my plans for the near future!