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CHVYMAN#9
03-16-2006, 21:50
Has Anybody Tried The Dual Electric Fans From Flex-a-lite? If So How About Some Info. And Feedback. Sounds Pretty Good,27 Hp And
No Fan Noise In Am.

BMDMAX
03-18-2006, 05:04
Has Anybody Tried The Dual Electric Fans From Flex-a-lite? If So How About Some Info. And Feedback. Sounds Pretty Good,27 Hp And
No Fan Noise In Am.

Those fans won't flow enough CFM to meet tow demands. For daily driving you would likely be ok but the stocker moves SERIOUS volumes of air for a reason.

I don't buy the 27 HP claim either.....

TLS
03-18-2006, 06:03
In cooler climates, and on gas engines that don't do any towing, they're working fine. I beleive the 27hp part.

I'm suprised that you Dmax drag guys aren't using them. Quicker warm ups and quicker cool downs at the track.

dmaxalliTech
03-18-2006, 22:05
In cooler climates, and on gas engines that don't do any towing, they're working fine. I beleive the 27hp part.

I'm suprised that you Dmax drag guys aren't using them. Quicker warm ups and quicker cool downs at the track.
Who says we wont try them though?

Kennedy
03-19-2006, 10:25
The power has to come from somewhere. Whether it's from the engine through the accessory belt system or the alternator, it has to come from somewhere.

I don't buy the 27 HP either...

JohnC
03-19-2006, 11:12
...I don't buy the 27 HP either...

We went through this a few years back on the 6.5 forum. If the fan really takes 27 hp, and you want the equivalent power from an electric fan, you'd need about 145 amps to drive the fans. (This, of course, would put a 27 hp load on the alternator...) Additionally, if you eliminate the mechanical fan, you'll need a way to kick on the electric fans for the intercooler and a/c condensor even if the coolant temp is OK..

AndyL
03-19-2006, 17:57
We went through this a few years back on the 6.5 forum. If the fan really takes 27 hp, and you want the equivalent power from an electric fan, you'd need about 145 amps to drive the fans.

John,

1 HP equals 746 watts. At 12 volts that makes for 1678 amps required to make 27 HP.

Dr Stev
03-20-2006, 01:05
Has anyone got any information from someone who has used one - especially during tow.

A quick check says that their claim is to recover 27 HP used by turning the fan mechanically and requiring only a 36 AMP draw when the electricla fan is needed (additional airflow required to cool.) Even that draw seems significant to me if you have conditions where ram air will not provide enough flow - stop and go traffic for instance.

I could agree with the 27 HP being used to turn the mechanical fan. But that brings another simple question that I don't understand - isn't the mechanical fan on a clutch? What does that really mean? Shouldn't the mechanical fan from the factory just freewheel when extra cooling isn't required?

I am curious about any experiences because electric cooling fans are common for non-tow vehicles to improve power and mileage. I would think there COULD be a problem when under tow that could be a concern for many of us.

JohnC
03-20-2006, 08:51
John,

1 HP equals 746 watts. At 12 volts that makes for 1678 amps required to make 27 HP.

Hmm, I dropped a decimal point! But I used 13.9 volts, which is closer to the nominal operating voltage of the system.

So, I guess the alternator won't be putting out 1450 amps, so the load is a lot lower (over a longer time...)

;)

When the clutch is not engaged it still puts some load on the engine, but the benefit is constant airflow over the intercooler and condensor. When the air temp coming off the radiator gets too high the clutch locks and the engine drives the fan directly. This is the only time the full 27 hp is tapped.

More Power
03-20-2006, 10:19
I saw the ad in the latest Summit Racing catalog, where the new Flex-a-Lite is being advertised for the 2001-2005 Duramax. The ad says 6000 CFM and a 27 HP reduction.

I don't see how a 6000 CFM fan can compete with a 10,000+ engine driven fan, but I would be interested in seeing the results from a fair test using the same vehicle towing at max GCVWR up a long steep grade in the hot summer heat. Two runs, one with the stock 10K+CFM fan and one with the 6K CFM electrics, then monitor the engine temperature with an auxiliary temperature gauge or Tech II scan tool. Max speed would also be interesting, to learn more about the 27 HP thing...

Someone should contact Flex-a-Lite, and ask about their comparison testing......:)

Jim

Claven
03-20-2006, 15:38
I have the flex-a-lite fans on my truck and have pulled trailers with no issues as of yet, haven't had them through the summer yet, but I have towed on days as warm as 60 deg f with absolutly no heat issues, but I do have good cab heat now. I'll keep you posted through out the summer. (yes, I live in canada, but we see 100+ deg f days here to).

As far as the volume, 6000 cfm vs 10,000 cfm, I am assuming that 10,000 cfm is at top rpm(3200) fully locked? Not sure though, but if this is correct, then at cruising speed (2000 rpm) it would equate to 6250 cfm when fully locked. Where as the electric fans are 2 stage, and can produce 6000 cfm regardless off engine rpm. If I remember correctly, the fans come on at 60%, then with a 10 deg f rise, they come on at 100%. Anyway, like I said I'll keep you all posted, and I'll be taking the stock fan with me this summer just in case I have to swap it back.(It's an ez job. 20 mins).

The kit comes with an A/C trigger so the fans come on with the A/C, a manual trigger "connection" (no toggle) to turn them on any time, (at the track). Also comes with indicator light "connections" (no light).

27 hp gain...well, definetly in situations when the stock fan would've been locked up, but overall...no. So far I think I'm the only one who has actually tried one, alot of people have input, but I thought I would try one for myself, and so far so good.

So, all that being said, I really like the fans. There is no noise, they don't rob hp, the engine warms up faster, and hopefully they work all summer.

hug
03-20-2006, 18:23
These fans are only good for up to 18000 gvw. I read this in there application table. So most of us would be to heavy. As a daily driver probably be fine.

More Power
04-02-2006, 17:05
Claven,

Keep us posted concerning your experiences with the electric fans, heavy loads and the upcoming hot summer temps. I just don't think the dual electrics can compete, but I'm open to actual on-road experiences. I'd also be interested in any fuel economy changes.

Otherwise, I saw an ad in a truck magazine recently for the Flex-a-Lite dual-electrics made for a Duramax application. The ad said the fan pair drew 36 amps when engaged, and that the 27-hp lost to the stock fan was with the Duramax running at 70-mph. I would bet that means in direct at 3000 rpm, and with an engaged fan-clutch.

What I haven't seen yet in their ads is a CFM comparison, or what the stock alternator "hot capacity" is (most 105 amp alternators can deliver about 85 amps when hot). Running on a hot night with a trailer, and with the A/C (and stereo & all other electrical accessories) pulls how many amps? Will dual alternators become necessary to reliably run the electric fans?

Just not enough info out there to form an opinion...

Jim

JoeyD
04-02-2006, 17:26
I saw the ad in the latest Summit Racing catalog, where the new Flex-a-Lite is being advertised for the 2001-2005 Duramax. The ad says 6000 CFM and a 27 HP reduction.

I don't see how a 6000 CFM fan can compete with a 10,000+ engine driven fan, but I would be interested in seeing the results from a fair test using the same vehicle towing at max GCVWR up a long steep grade in the hot summer heat. Two runs, one with the stock 10K+CFM fan and one with the 6K CFM electrics, then monitor the engine temperature with an auxiliary temperature gauge or Tech II scan tool. Max speed would also be interesting, to learn more about the 27 HP thing...

Someone should contact Flex-a-Lite, and ask about their comparison testing......:)

Jim
Funny you mention a test to find out the real answers. There is a guy in Montana who runs a hill climb test every year maybe we could get a hold of him and see if he would run one on his truck. He has run the same truck on the hill before with the mechanical fan so he would be a good canidate. Does anyone know this guy?

Claven
04-02-2006, 18:46
Claven,

Keep us posted concerning your experiences with the electric fans, heavy loads and the upcoming hot summer temps. I just don't think the dual electrics can compete, but I'm open to actual on-road experiences. I'd also be interested in any fuel economy changes.

Otherwise, I saw an ad in a truck magazine recently for the Flex-a-Lite dual-electrics made for a Duramax application. The ad said the fan pair drew 36 amps when engaged, and that the 27-hp lost to the stock fan was with the Duramax running at 70-mph. I would bet that means in direct at 3000 rpm, and with an engaged fan-clutch.

What I haven't seen yet in their ads is a CFM comparison, or what the stock alternator "hot capacity" is (most 105 amp alternators can deliver about 85 amps when hot). Running on a hot night with a trailer, and with the A/C (and stereo & all other electrical accessories) pulls how many amps? Will dual alternators become necessary to reliably run the electric fans?

Just not enough info out there to form an opinion...

Jim
Absolutely, I will keep you updated, because I found the same thing, just not enough info, and no one has road tested them, so I thought I would go for it, I've had it for about 5 months now and so for I like it,and I am still running the stock alternator with lots of extra electronics (x-box, 4 monitors, driving lights, the "4 headlights on" kit, fass pump and now fans) and still good. but I will definetly keep everyone updated.