Stock Fan vs Dual Electric Fans...with CFM #'s

Brandon#

Member
Joined
Oct 12, 2014
My water temp has been hovering around 205 degrees in stop and go traffic with the stock cooling system and the Precision FMIC. I decided to try and increase the airflow over the radiator by adding some dual electric fans to help keep the temp in check.

I opted for the Alradco Hybrid fan setup after reading many threads, and pm's with the vendor. The hybrid version came with the slim fan which gives more clearance for the turbo to intercooler piping.

I happen to have access to an instrument that measures airflow, so I thought it would be neat to test the before/after airflow.

Disclaimer!-This instrument is designed to test unobstructed openings. I enter the diameter of the opening that I am measuring and it calculates airflow. As we all know the fans are not a perfect circle of airflow. The motor and guard both block airflow. These numbers are for entertainment purposes only and should not be considered representative of the manufacturers advertised airflow.

I took airflow readings for each fan at several locations (12 o clock, 3 o clock, and 6 o clock) and took the average reading.

Stock 28 year old fan (15") - averaged 1500 cfm
Alradco hybrid (dual 11")-averaged a combined 3650

Side by Side comparison. After looking closer at the stock fan I noticed how poor of a design it is. The shroud does not cover the entire radiator, and there are large gaps where it does cover the radiator.




The "Extreme" Spal fan (11") measured around 2,300 cfm (This fan moves some serious air for an 11" fan!)



The "Slim" Spal fan (11") measured just over 1,350 cfm






I am very happy with the results of the Alradco fans. The airflow across the radiator is well over double what I had with the stock fan. My water temp has not been over 185 in this Houston heat yet. The fitment of the Alradco setup is better than stock IMO. I highly recommend this setup!
 
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I have Alradco's twin slim fan setup, GN1 radiator, 160 stat and RJC 325 FMIC. Today it was 85-90 degrees with 75%+ humidity and according to xfi my temp got up to 200 driving around town w/o AC on. Normally around 170-180. May need to go for that hybrid setup.
 
My water temp has been hovering around 205 degrees in stop and go traffic with the stock cooling system and the Precision FMIC. I decided to try and increase the airflow over the radiator by adding some dual electric fans to help keep the temp in check.

I opted for the Alradco Hybrid fan setup after reading many threads, and pm's with the vendor. The hybrid version came with the slim fan which gives more clearance for the turbo to intercooler piping.

I happen to have access to an instrument that measures airflow, so I thought it would be neat to test the before/after airflow.

Disclaimer!-This instrument is designed to test unobstructed openings. I enter the diameter of the opening that I am measuring and it calculates airflow. As we all know the fans are not a perfect circle of airflow. The motor and guard both block airflow. These numbers are for entertainment purposes only and should not be considered representative of the manufacturers advertised airflow.

I took airflow readings for each fan at several locations (12 o clock, 3 o clock, and 6 o clock) and took the average reading.

Stock 28 year old fan (15") - averaged 1500 cfm

Side by Side comparison. After looking closer at the stock fan I noticed how poor of a design it is. The shroud does not cover the entire radiator, and there are large gaps where it does cover the radiator.




The "Extreme" Spal fan (11") measured around 2,300 cfm



The "Slim" Spal fan (11") measured just over 1,350 cfm






I am very happy with the results of the Alradco fans. The airflow across the radiator is over double what I had with the stock fan. My water temp has not been over 185 in this Houston heat yet. The fitment of the Alradco setup is better than stock IMO. I highly recommend this setup!

Alradco needs to put you on their payroll. I mean really. Very good info
 
Nice to know the numbers. Just installed same setup in my car last week,cant believe the difference in temps,thanks for the info,Gene.
 
Alradco needs to put you on their payroll. I mean really. Very good info


Thanks, but I'd be happy with just a killer deal on their sweet aluminum radiator.

I was going to measure the sound level difference too, but I forgot to measure the stock fan setup. I was anticipating the dual fan setup to have that loud annoying aftermarket fan sound, but it doesn't. I was very pleased.
 
My water temp has been hovering around 205 degrees in stop and go traffic with the stock cooling system and the Precision FMIC. I decided to try and increase the airflow over the radiator by adding some dual electric fans to help keep the temp in check.

I opted for the Alradco Hybrid fan setup after reading many threads, and pm's with the vendor. The hybrid version came with the slim fan which gives more clearance for the turbo to intercooler piping.

I happen to have access to an instrument that measures airflow, so I thought it would be neat to test the before/after airflow.

Disclaimer!-This instrument is designed to test unobstructed openings. I enter the diameter of the opening that I am measuring and it calculates airflow. As we all know the fans are not a perfect circle of airflow. The motor and guard both block airflow. These numbers are for entertainment purposes only and should not be considered representative of the manufacturers advertised airflow.

I took airflow readings for each fan at several locations (12 o clock, 3 o clock, and 6 o clock) and took the average reading.

Stock 28 year old fan (15") - averaged 1500 cfm
Alradco hybrid (dual 11")-averaged a combined 3650

Side by Side comparison. After looking closer at the stock fan I noticed how poor of a design it is. The shroud does not cover the entire radiator, and there are large gaps where it does cover the radiator.




The "Extreme" Spal fan (11") measured around 2,300 cfm (This fan moves some serious air for an 11" fan!)



The "Slim" Spal fan (11") measured just over 1,350 cfm






I am very happy with the results of the Alradco fans. The airflow across the radiator is well over double what I had with the stock fan. My water temp has not been over 185 in this Houston heat yet. The fitment of the Alradco setup is better than stock IMO. I highly recommend this setup!
Was the oem fan running on low or hi-speed mode?
 
The Alradco piece looks really nice but I didn't have the budget for it.
The Dodge Intrepid fans are fantastic and very budget friendly , who knows how long it will last though....
They are a very nice alternative and keeps my car very cool

Bryan
 
The Alradco piece looks really nice but I didn't have the budget for it.
The Dodge Intrepid fans are fantastic and very budget friendly , who knows how long it will last though....
They are a very nice alternative and keeps my car very cool

Bryan
Phone guy is there certain years for the intrepid fans and will they work with a stock location intercooler ?
 
The Alradco piece looks really nice but I didn't have the budget for it.
The Dodge Intrepid fans are fantastic and very budget friendly , who knows how long it will last though....
They are a very nice alternative and keeps my car very cool

Bryan
I run them for years they haven't burned out yet well worth the $70, they move around 3000 cfm.
 
My Intrepid fans have been running for just over 10 years now, still perfect.
 
The Alradco piece looks really nice but I didn't have the budget for it.
The Dodge Intrepid fans are fantastic and very budget friendly , who knows how long it will last though....
They are a very nice alternative and keeps my car very cool

Bryan

I didn't want to risk overheating on a 20+ year old set of fans that I dug out of a junk yard, so I decided to splurge a few hundred.

Trying to save a few $ by using old used parts has bit me in the past. Some people have great luck with it, I am just not one of those people.

Also I think its good to support a vendor that contributes a lot to the TR hobby.
 
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Phone guy is there certain years for the intrepid fans and will they work with a stock location intercooler ?
I haven't had a stock location intercooler since 2007 so I can't tell you if it would fit but it is a pretty slim fan setup.

Bryan
 
I didn't want to risk overheating on a 20+ year old set of fans that I dug out of a junk yard, so I decided to splurge a few hundred.

Trying to save a few $ by using old used parts has bit me in the past. Some people have great luck with it, I am just not one of those people.

Also I think its good to support a vendor that contributes a lot to the TR hobby.
I get what you are saying about used stuff and more power to you if you have the money to spend 400.00 on fans. Like I said it looks like a nice piece....

I chose to spend my money in my engine , trans , rear end , turbo , nice gauges paint.........and a decent oil filtration system to protect the engine....

Bryan
 
Good job on the data. What were the "loads" (pressure drop) when the tests were run? Or was this just free-flow (unloaded)?
 
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