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Old 10-04-2008, 10:29 PM   #1
Critter
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Electric fan

How much air flow (CFM) would I need if I removed my stock fan and used an electric setup. Condidering I have a mild build 350 with A/C in South Texas heat.
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Old 10-05-2008, 06:14 AM   #2
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Re: Electric fan

All you can get.

Pulling air through is better than trying to push it through.
(don't know how you intend to mount though)
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Old 10-05-2008, 07:33 AM   #3
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Re: Electric fan

I had an aluminium be cool radiator, and 2, 11" Spal fans on my 502 Chevelle, and it would keep up with Florida summers. 3/4 up the gauge. If you go to www.spal-usa it will show CFM ratings. I think this is a case of more is better. Currently own a 69 SWB, and will be installing A/C soon. I am thinking about the 12" dual spal's, and their fan controller. I have a 4 row copper/brass radiator in my truck now, and with no A/C it does just fine

Last edited by cparman; 10-05-2008 at 07:34 AM. Reason: typo
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Old 10-05-2008, 07:57 AM   #4
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Re: Electric fan

...a shroud is key also.
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Old 10-05-2008, 08:30 AM   #5
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Re: Electric fan

There was an electric fan install in the truck section a while back. The setup was from a late model Jeep. I am thinking about giving it a try.http://67-72chevytrucks.com/vboard/s...d.php?t=254617 I finally got the link to work.

Last edited by 1972CST; 10-05-2008 at 08:38 AM.
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Old 10-05-2008, 08:35 AM   #6
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Re: Electric fan

71 rat did a good thread on a Chrsyler/ Jeep fan install, stock fan and it bolts rite into our stock shroud. I ended up buying his, so I will post up pics when I get it. The unit new sells for about 50, but I don't know the cfm's.

CST and I must have typing at the same time
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Old 10-05-2008, 08:42 AM   #7
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Re: Electric fan

Thats what I was thinkin. I called my local dealer and they said it would be against the law for them to sell me a "recalled" part. I am not trying to buy the take-off fans, I want a brand new one.

Where did you get yours jaros44sr?

Last edited by 1972CST; 10-05-2008 at 08:44 AM.
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Old 10-05-2008, 09:28 AM   #8
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Re: Electric fan

Quote:
Originally Posted by 1972CST View Post
Thats what I was thinkin. I called my local dealer and they said it would be against the law for them to sell me a "recalled" part. I am not trying to buy the take-off fans, I want a brand new one.

Where did you get yours jaros44sr?
I got mine w/shroud from 71Rat, there was a web site with thread to Chrysler site, and guys were buying thru that

Thread is titled...another cheap electric fan build
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Old 10-05-2008, 01:06 PM   #9
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Re: Electric fan

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Originally Posted by vtblazer View Post
All you can get.

Pulling air through is better than trying to push it through.
(don't know how you intend to mount though)
I am wanting to pull the air. (unless someone gives me a good reason otherwise) I have been seeing alot of single and dual fan "kits" that come with shrouds. Most of them will have 2 or 3 different options based on CFM flow. I want to make sure I get an adequate kit, but at the same time I didn't want to spend twice the amount of money on something inteded for a bigblock race engine and it be overkill for my setup. I guess in this case too much air is WAY better than not enough.

I have seen formula that tell you how to calculate CFM using HP, A/C and radiator dimentions and material. I just can find them right now.

Quote:
Originally Posted by 1972CST View Post
There was an electric fan install in the truck section a while back. The setup was from a late model Jeep. I am thinking about giving it a try.http://67-72chevytrucks.com/vboard/s...d.php?t=254617 I finally got the link to work.
I have always liked this setup, read about it when he originally posted. I might try to go this route. It seems to handle the job pretty well.
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Old 10-05-2008, 03:06 PM   #10
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Re: Electric fan

with my last car, I started with one 16" fan. would not keep up with Fla. heat, and was very noisy. The dual 11" kept up on all the the very hot days, and was way quieter. I drive my 67 Chevelle, zz502, 700r4 ETC. to the Googuys show 2 years ago, and the heat index was 110. Driving from downtown Jacksonville to my home at the beach, the guage was a bit over 3/4. made me uncomfortable. I think that unless you are running a bunch of motor 2 11" or 12" would keep up just fine with Texas heat.

Last edited by cparman; 10-05-2008 at 08:21 PM.
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Old 10-05-2008, 08:23 PM   #11
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Re: Electric fan

hopefully here is a picture of what a mouth full 2 11" dual fans and a zz502 are in a 67 Chevelle
"
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Old 10-05-2008, 08:55 PM   #12
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Re: Electric fan

Lets see the rest of the car!
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Old 10-05-2008, 10:25 PM   #13
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Re: Electric fan

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Originally Posted by 1972cst View Post
Lets see the rest of the car!
no kidding!
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Old 10-06-2008, 05:37 AM   #14
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Re: Electric fan

Camaro fan, two position toggle (high/low), relay's, LED lights and a stock shroud.

Works great 75% of the time on low and is very quite, put it on high and you can watch the needle drop.

Used a old school ignition resistor to provide the 4.5 volts on low.

Fan draws 4.2 amps on low and 10.5 amps on high.
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Old 10-06-2008, 09:46 AM   #15
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Re: Electric fan

I have ran Flex-a-lite fans for years and have ahd good luck with them so far.
With my old 350 I used the "black magic" single electric fan w/ a clutch fan off the water pump. So the electric was only turned on during the summer heat wheeling the trails.
Now with a BBC I use the dual 13.5" Flex-a-Lite:

http://www.flex-a-lite.com/auto/html...-electric.html

This fan is my only fan and I have had zero heat issues, works great.
As for CFM I would not get any thing below 2500CFM.
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Old 10-06-2008, 09:53 AM   #16
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Re: Electric fan

Quote:
Originally Posted by vtblazer View Post
Camaro fan, two position toggle (high/low), relay's, LED lights and a stock shroud.

Works great 75% of the time on low and is very quite, put it on high and you can watch the needle drop.

Used a old school ignition resistor to provide the 4.5 volts on low.

Fan draws 4.2 amps on low and 10.5 amps on high.
What year Camaro fan, the last years 98-05 or whatever? I'm assuming its from a V8. I kinda like the look of the factory shroud.
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72 Chevy CST K5 HIGHLANDER BLAZER Getting a 6.0,NV4500,NP205,14BFF (Currently laying all over the place in little pieces)
72 Chevy swb step-side "LS" 6.0 Here's a build thread of sorts
2002 HD2500 Crew Cab, 8.1L Allison 4x4 Daily Driver

Check it out www.lsdyno.com

Last edited by Critter; 10-06-2008 at 09:54 AM.
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Old 10-08-2008, 02:51 PM   #17
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Re: Electric fan

That Jeep fan set up is definitely the trick way to go. I got really lucky and found one at a swap meet for only 5 bucks! I was able to I.D. it thanks to this forum! I installed it on my 71 camper van (same shroud) and it works great. BUT, if you cant find a Jeep fan, here's a different idea I did to my Blazer and it works even better. http://67-72chevytrucks.com/vboard/s...d.php?t=282793
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