[vaccaraj]

i'm thinking of putting an electric fan on my car. i want it to be a pusher fan to be used in conjuntion with my stock fan. there is a lot of stop & go traffic in my area and even though i've got my cooling system problems under control, at idle and low speeds the temp. has a tendency to climb somewhat. i'm thinking of hooking it up to the brake pedal switch so its used when needed. i guess what i'm looking for is a name brand for a good electric fan. has anyone done this to any of their cars.
tony

[vaccaraj]

i'm thinking of putting an electric fan on my car. i want it to be a pusher fan to be used in conjuntion with my stock fan. there is a lot of stop & go traffic in my area and even though i've got my cooling system problems under control, at idle and low speeds the temp. has a tendency to climb somewhat. i'm thinking of hooking it up to the brake pedal switch so its used when needed. i guess what i'm looking for is a name brand for a good electric fan. has anyone done this to any of their cars.
tony

[Half-Inch Stud]

Go to the junkyards and get two nice, clean GM fans from late-80's, early-90s cars. You'll know them to be big by the full square shroud with rimmed fan. Fan may have straight blades, or S'd blades. The S-curve in each blade is supposed to be quieter. Sounded equally loud to me. The straight blades are better balanced, and have better efficiency - by design.

Get the GM electrical wiring and fender-well relay too because that's high quality wiring.
I paid the junkman $5 each, 5 years ago. JC-Witney had the same sized-items for $119. Pepp Boys had something similar for >$100 too. I like good-used factory developed parts, so the $5 items met my goals.

Don't under-estimate the air pulling requirement at idle. The horsepower given to the mechanical fan goes directly to the fan-wind drag..OK 80%. Think of the Amps at 12Volts needed to "rob" 2HP from using the electrical fans. At 754 Watts/HP, you cannot draw such current to push/pull the same air flow.

Seems the big ponchos will climb temperature in a hurry at the red lights. Think I'm kidding? - Tried one elecfan, then two, drew more than 60Amps and could smell my alternator after 2 weeks.
Then switched to the fluid clutched fans, was a believe in that until I locked 3/3 [new - thanks Pepp Boys] clutches. The third time caused my water pump to crack-out during a 2-3 highway upshift [was on my way to my brother's wedding rehersal]. Real neat story there about how the pump doesn't gush at the bearing at highway speeds. While at idle it gushes like an uncapped garden hose.

I'm back to the factory flex fan. No cooling troubles - just wondering if/when my aluminum water pump is going to shatter from shock.

------------------
"his peg-leg got woodworm , and broke into three"--G. Baker

[72LeMConvt]

1/2 Inch - I'm confused now. You start off your reply with detailed, well thought out recommendations for electric fans. Then you give some info that seems to shy away from electric fans. Then you give horror stories that definitely point away from electric fans and wind up back at factory original.

But the junkyard scrounging advice seemed so specific.....Where should this novice (me) go from here?

[Half-Inch Stud]

Soon grasshopper, you understand how hot the kettle is.

Stick with the engine-driven fan for street. Air conditioning : forget the elec, [factory A/C cars used clutch fan] yet stay with mech flex fan. Some folks have been fortunate to have the clutch fan survive. I have not. New info: try looking up the big-block Chevy truck clutch fan part. Supposed to be strong clutch. I do not know yet.

IMOP; The electric fan(s) is/are good to run at the racetrack.

[Tim Corcoran]

vaccaraj,

I have had great success with the GM factory thermal clutch and the 17" A/C seven blade fan. For a street car I wouldn't use anything else. The GM thermal clutch fan does not consume as much hp as other fans because it free wheels at high rpm and when the engine is cool (when not needed). Make sure you are using a good 4 core radiator and a shroud also. A Desert Cooler or an aluminum radiator are also great improvements over the stock radiator. If everything else is working and you want to use an electric as a back up in traffic I suggest a 16" Spal and use a 180 degree thermal switch rather then your brake light switch. The thermal switch can be installed in the intake manifold. The best install would be with a relay. I also recommend a Robert Shaw 160 thermostat. There is one more thing that you may want to try. When you run a high stall converter on the street you are creating more heat in the transmission oil. This heat is transferred to the cooling system. This additional load on the cooling system may be too much for a factory system. Running a good stack plate oil cooler prior to the radiator just may be worth a try. I use a large capacity oil cooler and don't even run it through the radiator and I have had great success with this set up. Good luck.

Tim Corcoran

[This message has been edited by Tim Corcoran (edited 09-26-2000).]

[Tim Corcoran]

vaccaraj,

I just went back and read some of your old posts on your cooling problems. I think a large capacity aluminum radiator would solve your problem once and for all. Bee Cool makes a direct bolt in but it's expensive. Griffin makes top of the line radiators and will require some minor mods/fabrication. A custom made may be your best bet and it's cheaper than a Bee cool. Jim Hand has used the Griffin's with good success. I believe that Griffin is the only one's that have 1" tubes in their cores and don't sell their cores either.

Tim Corcoran