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Technical Information => General Tech => Topic started by: cyris426 on February 01, 2015, 08:21:12 PM

Title: Enough CFM?
Post by: cyris426 on February 01, 2015, 08:21:12 PM

Hey guys,

I have a 1984 GSL-SE that i put a ford 302 into. I am looking at cooling it and am curious what CFM fan is needed. The rad core is 11inch by 23inch and is a 3 core. I am looking at a fan that will fit on the core (11x23) and can pull enough air. I plan on building a shroud also. It is a stock 302, prolly makes 250 or so torque and 150 or so horsepower. There is 2.7 or so inch's of clearance in between the electric water pump and the rad which limits the size of fan.

I am looking at this fan: http://www.jegs.com/i/SPAL/063/30100364/10002/-1?parentProductId=2861424 (http://www.jegs.com/i/SPAL/063/30100364/10002/-1?parentProductId=2861424)

Is this going to be enough CFM with a shroud? Or will i fall short in hotter temps? Summer gets about 30 or so Cecilius here.

Thanks

Title: Re: Enough CFM?
Post by: spacevomit on February 01, 2015, 09:05:21 PM

Static pressure is more important than CFM for a cooling fan.

Title: Re: Enough CFM?
Post by: zbrown on February 01, 2015, 09:08:24 PM

Look at the amp draw of a fan if you want an idea of its capacity. Don't believe crap you read on flow rates

Title: Re: Enough CFM?
Post by: spacevomit on February 01, 2015, 09:38:09 PM

^Agreed. Some companies give a graph of CFM amperage and pressure.

Title: Re: Enough CFM?
Post by: cyris426 on February 01, 2015, 10:22:33 PM

They say that fan is 7 AMPS.

Title: Re: Enough CFM?
Post by: gnx7 on February 01, 2015, 11:32:38 PM

A Ford Taurus Fan supposedly pulls 4000 cfm.  I have a 60amp relay on mine. 

I would ping the other V8 FB guys to see what they run before buying anything.  That is a small dimensional radiator... but 3 core is good!
Not many 10" fans that fit your core are going to pull much at all.

Title: Re: Enough CFM?
Post by: cyris426 on February 02, 2015, 09:53:50 AM

How do i ping them? What does that mean?

Thanks

Title: Re: Enough CFM?
Post by: zbrown on February 02, 2015, 09:59:22 AM

7 amp isn't gonna do shit.   Find something else. An OEM app fan is usually your best bet

Title: Re: Enough CFM?
Post by: cyris426 on February 03, 2015, 12:25:05 AM

That's as good as i can get for that low profile. There is only 2.6 or 2.7 or so of clearance in between the rad and the water pump. Any other ideas?

Title: Re: Enough CFM?
Post by: cyris426 on February 03, 2015, 12:34:09 AM

http://www.etrailer.com/Radiator-Fans/Derale/D16112.html (http://www.etrailer.com/Radiator-Fans/Derale/D16112.html)

What about this one? It is rated at 14 amps and is low enough profile to fit

Title: Re: Enough CFM?
Post by: Bowtie7 on February 03, 2015, 10:01:04 AM

Ive been using fbody fans forever and had great success with them. I run a 30A relay on each fan. FC's will not overheat in stop and go summer traffic with a/c on. Temp never above 210.

Title: Re: Enough CFM?
Post by: spacevomit on February 03, 2015, 10:24:50 AM

What they say about electric fans not using engine power is false. It just happens at the alternator.

Title: Re: Enough CFM?
Post by: cyris426 on February 04, 2015, 10:35:57 AM

What is an fbody fan? Also, the electric fan is a must since there is very limited room for clearance without modifying the large bar that runs from side to side near the front of the car.

Title: Re: Enough CFM?
Post by: cyris426 on February 04, 2015, 10:38:11 AM

http://www.etrailer.com/Radiator-Fans/Derale/D18214.html (http://www.etrailer.com/Radiator-Fans/Derale/D18214.html)

This one has high amp rating and may just barley fit.

Title: Re: Enough CFM?
Post by: cyris426 on February 13, 2015, 12:46:55 AM

Anyone know anything more about this? Cant get this car to drive without a cooling system working.

Title: Re: Enough CFM?
Post by: cyris426 on February 16, 2015, 10:46:58 AM

bump

Title: Re: Enough CFM?
Post by: spacevomit on February 16, 2015, 10:57:56 AM

I'm not saying you should run a mechanical fan off the FEAD or anything... Just noting that the car's electricity is generated mechanically as well. Derale, Spal etc should be good, name-brand fans. The curved blade ones would be good, more blade area for a given size. What else do you want to know?

Title: Re: Enough CFM?
Post by: quinns on February 16, 2015, 01:38:45 PM

Quote from: spacevomit on February 16, 2015, 10:57:56 AM

I'm not saying you should run a mechanical fan off the FEAD or anything... Just noting that the car's electricity is generated mechanically as well. Derale, Spal etc should be good, name-brand fans. The curved blade ones would be good, more blade area for a given size. What else do you want to know?

FEAD - Front End Accessory Drive

Thanks for teaching me something new today. I had to google wtf that was.

Title: Re: Enough CFM?
Post by: Cman on February 16, 2015, 01:44:30 PM

Quote from: cyris426 on February 04, 2015, 10:35:57 AM

What is an fbody fan? Also, the electric fan is a must since there is very limited room for clearance without modifying the large bar that runs from side to side near the front of the car.

I'll jump in and say that this is the full fan and shroud from a 1998 to 2002 Camaro/Firebird. This is a 2 fan system. I didn't use this but have friends who did with success.

Steve

Title: Re: Enough CFM?
Post by: cyris426 on February 19, 2015, 10:51:51 AM

I think i will build a shroud out of fiberglass or perhaps aluminum.

This is a derale fan that looks like it will clear in depth. http://derale.com/products/electric-fans/universal-electric-fans/h-o-extreme/aluminum--10an-o-ring-plug-detail (http://derale.com/products/electric-fans/universal-electric-fans/h-o-extreme/aluminum--10an-o-ring-plug-detail)

Any luck with that you think?

Title: Re: Enough CFM?
Post by: coltboostin on February 19, 2015, 05:41:08 PM

Is it fully ducted?

Will you road race the car?

Cooling is so relative to set up and intended use its not funny.  I have seen swap cars live life fine with a AFCO VW radiator (very small) and some cars need a monster radiator to keep things in check.

Title: Re: Enough CFM?
Post by: cyris426 on February 19, 2015, 08:39:28 PM

Derale told me it is 14.2 amps and jegs has it for 127$.

I will drive it hard sometimes, but definitely not road race. I don't really know what ducted means... I was planing on building a shroud around the fan and rad to keep the flow up so it is not wasted out the side. In the summer it may get 90 F here max. I just don't wanna buy it and find out it isn't going to cool it enough. This is a mostly stock 302 also, not a giant 400 horsepower monster.

Thanks