Electric fan size & CFM?

[heyman421]

My z22 has a clutchless fan, and i do primarily highway driving.

Lucky for me, clutchless fan means my water pump pulley and fan are seperate, so i'd like to just leave the fan off and add an electric one with a 180 degree thermostat instead.

I was curious what size/CFM those of you with electric conversions are using, whether or not you're using the original fan shroud, and whether or not you experience any overheating in stop and go, or when stopped (i don't do much 'idling' but it's a consideration just in case.)

[captainzeros]

On my '81 Z22 truck I have a little wiener of a geo metro fan mounted in front of the radiator wedged behind the grill. No idea on the CFM, but it's a 12" diameter unit no more than an inch thick. No overheating problems at all, even idling in 100+ weather last summer.

[breadbox]

Is your clutch fan not sufficient. On my truck with the stock shroud in pace it pulls alot of air. And figuring that the fan only actually does something at low speeds and idle, why switch to e-fans? they can be an expensive swap to get right. I.E. wiring with a stat so it turns on when it is supposed to. wiring it to run all the time isn't great and a toggle switched fan is a horrible idea, I like how clutch fans work.

With that said, Try to find one off a maxima with the fan that looks kind of off balance and all the blades are connected by a large ring. This is a pretty good design of efan that pulls a lot of air but doesn't put a huge load on the system. Center it mount it flush and it should be perfect. If I have to I can try to find one in my garage from one of my 240sx projects and take a picture. but I hope you can find what I'm talking about.

[heyman421]

My z22 has a clutchless fan

Summit racing's down the street from my shop, and they have 14" ~1300cfm fan/relay/push-in thermostat packages for under $100.

I'm sure if a 10" is doing a job in 100 degree weather, a 14" should be ok without the shroud in Ohio.

[flinterman2000]

Is your clutch fan not sufficient. On my truck with the stock shroud in pace it pulls alot of air. And figuring that the fan only actually does something at low speeds and idle, why switch to e-fans? they can be an expensive swap to get right. I.E. wiring with a stat so it turns on when it is supposed to. wiring it to run all the time isn't great and a toggle switched fan is a horrible idea, I like how clutch fans work.

Clutchless fans are rather noisy and are a constant drain of engine power. Heres what I did. Unfortunately its all custom so it was a little expensive - US650 - for it all.





Note the temp sensor on the top tank of the radiator.

When I get the truck back from the electrician I post the wiring done.

[heyman421]

Wow. That looks... complicated!

I've used the fan kits from summit for a fuel cooler on my old turbo diesel, and they basically just zip-tie to the radiator.

If i give it a whirl and it's successful, i'l post pictures.

The other option at this point is to simply source the newer water pump with the clutch, but the price is pretty close and since i have the non-clutch pully already it would be just as easy for my to go electric.

My truck's not even running right now (view my head gasket thread) so this isn't a top priority, but considering i only have 4 gears, i think an electric (or even just a clutch-type fan) cold realistically gain me 1-2mpg on the highway for very minimal effort.

[captainzeros]

Note, I went electric because my original plastic fan broke and lost a blade. Local pick-n-pull didn't have any close enough nissan fans to use, but an electric fan was I think 15 whole dollars. I didn't wire in ANY kind of thermostat at all, because frankly I do not care if my fan spins all the time and a thermostat switch would've involved buying more parts.

I don't know if it affected my mileage in any way, but it DID make the engine rev a lot more freely and made me grin pretty big as I revved the piss out of it in my driveway and annoyed my neighbors, definitely worth the $15 junkyard fan cost.

[flinterman2000]

Where I am, the fan running constantly would encourage the engine to run too cool and would run rich due to the ECU, even though I left the thermostat in. Also I will need the extra air movement as its now turboed soon to be inter-cooled.