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Discussion Starter · #1 ·
My AC condenser sits about a half inch in front of my radiator. I used to have a stock mechanical clutch fan and shroud that pulled air in, and I also had a small electric fan in front of the condenser to ensure airflow. The clutch was probably not working well for some time. I am not changing out the system to use a dual electric set of fans and shroud in a puller configuration and have removed the fan in front of the condenser. Should I try to seal the gap between the condenser and radiator to make sure the fans are not bypassing the condenser, or will this gap be ok. My fans combined will pull around 2,500 cfm at full speed. I will be using PWM control for the fans, so even on low speed should be pulling 1,200 cfm.
 

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hi
air flow will be sucked via the gap between the condenser and radiator . To solve this is to use what all a/con kits use is square peel and stick foam ,installed between gaps . The engine will be ok but the condensor will not cool very well if the foam is not installed .

2500 cfm is only modest and regarded as bare minimum . What is the fan make model your using ??
 

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Brushed Axial Fans - SPAL (spalautomotive.it)
SPAL_10thEd_FansAccessories (adobe.com)
your model
VA10-AP50/C-25A or 30101504
better
VA10-AP70/LL-61A or 30102029

The telling factor is amperage at only 10 amps ,its not alot . re 1090cfm
13-15 amps is average 1200-1500cfm
20 amps for a high performance fan 1400-1700cfm

Above is with no radiator air flow restriction
Best way to do comparo is at 1/2 inch or 12.5mm water depression . Gives a reading under load .
 

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I just sold a '78 Malibu wagon with twin Spals, not sure of size but each one had its own 30 amp relay. Another thing to take into account is the alternator output needed to support these. The wagon had a 220 amp unit that would only charge right at aound 12v at idle with cans running and a/c on. It jumped up to 14.2 over 1K rpm, but that was no help in traffic. It also had a FITech fuel injection unit that I hated. It cooled well but never ran as well as I thought it should have and both were more trouble than they were worth, and even withe a razor tune on a stock 350/290 crate motor with a 700R4, only tuned back 16 mpg on the highway. That combo with a Q-Jet would hit 20.
I got it built like this, but if I'd kept it, I would have swapped to a good fan with clutch and shroud and a Quadrajet. Newer is not always better...
 

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We need a lot more info to be able to advise you correctly
1. What type of Rad / Alum or Metal and how many Rows of Tubes ??
2. Is the Rad the biggest that can fit in your Car ?
3. Does the Shroud have Rubber Hwy Flaps ? AND does it cover all of the Rad Core ??
4. What size of Thermostat are you running ?
5. Provide a link for the Efans/Shroud Unit !!
6. Does the A/C Condenser cover the whole Rad Core ?
Having the A/C Condenser that close to the Rad Core means the Heat from it is being passed on to the Rad Core !!

This is a GOOD READ

Pics of the Front / Grill Side of the Rad and of the Engine Side of the Rad is also needed
 

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hi
Once the OP can answer questions only then will answers be accurate .
What happens most of the time is
combo 1 ,,elec fans undersize and huge rad core -- works for most
combo2 ,, stock core with high performance fans --works for most
both achieve the same thing reducing BTU `s [measurement of heat]

When things are MAX power ,big fans and big cores rock . The choice becomes between 2 version of fans PWM brushless or large brush type fans
Delta PAG

Minimum of 100amp alternator
 

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Discussion Starter · #11 ·
I have a Griffin 2 row aluminum exact fit radiator. It has the 28" wide by 17" core, which was what Chevy used for big blocks and L79 engines. I do not yet have the shroud, but believe it does have highway flaps. The shroud will cover the entire core face. I am running a 180 degree stat, and the engine is a ~425 hp SBC with manual trans. Water pump and pulley configuration is stock, no under drive pulleys. Alternator is rated for 115 amps output. Here is the link to the fans they proposed to install. Griffin Radiator Accessory PF-22 . I can keep the 14" fan currently mounted in front of the condenser core, which moves another 900 cfm or more. It is in pusher configuration. Am thinking of upgrading the dual puller fans to this SPAL Automotive USA IX-30102038 Spal Electric Fans | Summit Racing, which would give me around 3,600 cfm, plus the pusher fan. I will be using PWM control for the fans as well to help manage the amp draw. I realize the condenser passes much of its heat to the radiator, but have to live with the constraints the packaging around the grill and radiator support area imposes. You guys opened my eyes to the need for more airflow. I am aware of fan ratings at zero static pressure, but it can be hard to find fan curves to accurately compare performance, and even harder to measure the static pressure drop in my radiator system currently. My other thought is that having fans in front and behind the radiator will, to some extent, negate but not eliminate the static pressure drop across the core. Thanks for all the input so far. It has been really useful.
 

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I have a Griffin 2 row aluminum exact fit radiator. It has the 28" wide by 17" core, which was what Chevy used for big blocks and L79 engines. I do not yet have the shroud, but believe it does have highway flaps. The shroud will cover the entire core face. I am running a 180 degree stat, and the engine is a ~425 hp SBC with manual trans. Water pump and pulley configuration is stock, no under drive pulleys. Alternator is rated for 115 amps output. Here is the link to the fans they proposed to install. Griffin Radiator Accessory PF-22 . I can keep the 14" fan currently mounted in front of the condenser core, which moves another 900 cfm or more. It is in pusher configuration. Am thinking of upgrading the dual puller fans to this SPAL Automotive USA IX-30102038 Spal Electric Fans | Summit Racing, which would give me around 3,600 cfm, plus the pusher fan. I will be using PWM control for the fans as well to help manage the amp draw. I realize the condenser passes much of its heat to the radiator, but have to live with the constraints the packaging around the grill and radiator support area imposes. You guys opened my eyes to the need for more airflow. I am aware of fan ratings at zero static pressure, but it can be hard to find fan curves to accurately compare performance, and even harder to measure the static pressure drop in my radiator system currently. My other thought is that having fans in front and behind the radiator will, to some extent, negate but not eliminate the static pressure drop across the core. Thanks for all the input so far. It has been really useful.
Perfect for Efans
Can you post a pic or Online Site of it ?
is it made of Fiber Glass/Plastic ?? I hope not Metal !!
I run a 160* Thermostat so it is Fully Open at 180* Temps
Very Good
Not Good as it adds to the Restriction of Air Flow
thru it then the Condenser then the Rad /
something that impedes the Air Flow that the Puller Efans are trying to Pull Ait thru
Close to fitting with the Best Quite Efans possible SPAL 30102130: Dual 12" High-Performance Fan 12V - JEGS High Performance 3200cfm
What I would use if I had a Rad Core 28" x 17
" Flex-a-lite 116524 Flex-A-Lite Direct Fit Electric Fans | Summit Racing 4600cfm

If you can get the Condenser a little further away from the Rad Core and Down Lower
it will not pass as much direct Heat to the Rad core
 
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