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$200 K5 (454 K5 now) *too much junk in the trunk

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6872xtc said:
Do you suppose that if the fans are too small, they could also restrict airflow when speed is high enough to not need the fans on? As in too small of holes in the shroud causing a restriction?
I would just think that you would see a better drop in temperature over 45 mph.
:dunno:
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I believe he does have that problem because I think mine does the same thing even with the 15” fans. I want to setup a fan kill switch in the cab and see what happens. Because my temps will climb when on the freeway to the point I have to kill the a/c.
 
For point of reference, the fan on my rzr is a 12” spal and it’s a 1000cc engine. I’d say a big block would need way more air.
 
On the Cummins X12s at work we run 10 18” fans, I agree that the 12” probably aren’t big enough, I for one prefer a mechanical fans when possible.
 
Fastereddie said:
I believe he does have that problem because I think mine does the same thing even with the 15” fans. I want to setup a fan kill switch in the cab and see what happens. Because my temps will climb when on the freeway to the point I have to kill the a/c.
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That would be good R&D.
Didn't the factory put pressure relief flaps in some of the shrouds? Or am I remembering incorrectly?
 
6872xtc said:
That would be good R&D.
Didn't the factory put pressure relief flaps in some of the shrouds? Or am I remembering incorrectly?
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100%. My existing fans have some flaps but maybe not enough. I know the ss Camaro fan has a bunch of little flapper doors.
 
6872xtc said:
Do you suppose that if the fans are too small, they could also restrict airflow when speed is high enough to not need the fans on? As in too small of holes in the shroud causing a restriction?
I would just think that you would see a better drop in temperature over 45 mph.
:dunno:
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I think so0. Lots of dual fans are offset, with a flap above the fan to let free flow air through, That would be another part to produce and install so china just stamps some louvers in that spot.
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Since you're not running ac you should be way cooler. My previous temp post for my truck is running dual ac, I run a bit hot for my liking, but cooler than you in higher ambient.
Is this a new engine too?
 
HankScorpio said:
Never shut off is fine for now breaking things in but not for the long term. I would like to set one fan to come on with the thermostat and then the second fan to come on around 200. I don't currently have enough fan for that.

What fans are you running? Big block?
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I’m running a set of fans and aluminum radiator from entropy radiator on a relatively stock 454. The fans are own controlled so they ramp up/down speed as needed. Motor ran fine through the desert in needles, CA in June (100’s). Though the rear axle started overheating and puked oil up through the breather.

Are your fans shrouded? Maybe related to that if not. Edit: I see the pic now. That’s weird, it should be running much cooler than it is.
 
It’s not a gen V big block is it? That’s what I’ve got in my shortbed k10 and it runs hot
A.F….
 
Wes Harden said:
Since you're not running ac you should be way cooler. My previous temp post for my truck is running dual ac, I run a bit hot for my liking, but cooler than you in higher ambient.
Is this a new engine too?
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New engine, new cooling system.
 
When looking at fans you need to look at the CFM and also the amps or watts.

There are some 12" fans that flow more than 14" fans. And getting anything bigger than dual 14" on a 28"" wide radiator will be difficult, even if you offset them, because a 16" fan can only be offset 3" and that won't make the pair 4" narrower.

I have the Derale dual 12" fans with the flaps you showed above, and I have sold a few sets of those too, they are good fans that flow a lot of air, a set of them keeps my 632 cool, though I have no AC.

I have windstar fans on my truck, they work pretty well too, expecially for the price of a used set if you can find them.

Beware of fans that are over rated, I tried a set of dual 14" fans that supposedly flowed 4000 cfm, but they were only 120W, which is only 10A each. They would not keep a 502 cool on hot days. A set of Derale fans that are 14" also, are rated at 4200 cfm, but use 265W each! I don't believe that two different S blade fans have that different of efficiency, one does not make 95% of the airflow with 45% of the power consumption with the same size and shape of blades, I think they are lying and the Derale are speaking the truth.

For aftermarket I would stick with Derale or Spal. I can get you a set if you like.
 
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folkenheath said:
When looking at fans you need to look at the CFM and also the amps or watts.

There are some 12" fans that flow more than 14" fans. And getting anything bigger than dual 14" on a 28"" wide radiator will be difficult, even if you offset them, because a 16" fan can only be offset 3" and that won't make the pair 4" narrower.

I have the Derale dual 12" fans with the flaps you showed above, and I have sold a few sets of those too, they are good fans that flow a lot of air, a set of them keeps my 632 cool, though I have no AC.

I have windstar fans on my truck, they work pretty well too, expecially for the price of a used set if you can find them.

Beware of fans that are over rated, I tried a set of dual 14" fans that supposedly flowed 4000 cfm, but they were only 120W, which is only 10A each. They would not keep a 502 cool on hot days. A set of Derale fans that are 14" also, are rated at 4200 cfm, but use 265W each! I don't believe that two different S blade fans have that different of efficiency, one does not make 95% of the airflow with 45% of the power consumption with the same size and shape of blades, I think they are lying and the Derale are speaking the truth.

For aftermarket I would stick with Derale or Spal. I can get you a set if you like.
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For sure fans can have way different efficiencies. I’ll have to measure one but they aren’t more than 12”, and each one will pop a 20A fuse when it turns on at full speed. It was the reason I needed a PWM controller so I could slowly turn them on.
 
bp71k5 said:
For sure fans can have way different efficiencies. I’ll have to measure one but they aren’t more than 12”, and each one will pop a 20A fuse when it turns on at full speed. It was the reason I needed a PWM controller so I could slowly turn them on.
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I agree, S blade fans are more efficient than straight blade fans, and some motors are more efficient, but two S blade fans of the same diameter both brushed motors, no way does it flow the same CFM at half the wattage, especially when they come from overseas. I trust the US made fans. I'll know this week if it fixed the issue, it's supposed to be 97 this week.

Those fans you have that will pop a 20A fuse surely flow way more than a 8A fan of the same size, that is what I am trying to say. If he has some overseas fans with low wattage, they aren't enough, despite what airflow they claim.

By efficiency I am talking cfm/watt or cfm/amp in a 12V system. Those overseas fans claim 200 cfm/amp, and the Derale are 95 cfm/amp, I believe the Derale. If they are both telling the truth, then 4200 cfm vs 4000 cfm won't change anything. I bet the overseas fans are more like 2000 cfm, which is not enough.

The fans in my regal use over 20A per fan no question, and the fans in my truck are close to that, I think just under. When I had LS fans and a small block I could feed them both with one 30A fuse, but not the windstar fans I had to go to with the big block, the LS fans wouldn't keep it cool. Hooked up windstar fans and it popped the 30A fuse. Upgraded the wiring and the problem was solved.

Also, when they put louvers in the fan shroud, that reduces the effectiveness, because the fan can just pull air through the louvers and blow it right back out, and that air never goes through the radiator. Derale has flaps that only allow the air to go out the vent, but not in.

I also set the fans to turn on/off at 5 degree different temps, so they don't both turn on at the same time and pull down the electrical system.
 
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I have to agree with most here there's something not right, you shouldn't have that much trouble cooling it.
I would first doubt you Chinese fans are doing their job but don't dismiss the whole system, make sure coolant is flowing properly, no restrictions, water pump with correct rotation and no air in the system.
 
I pretty much always run a high flow thermostat, not just for the flow, but because the cheap parts store thermostats are junk out of the box or shortly after too often.
 
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