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Dukking Around
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Discussion Starter #1
I'm curious if I'm able to put my stock fan and shroud back on my truck to aid in cooling. Currently im running dual 11's with a thermostatic switch set at 185/210. I'm also running a 50/50 mix with water wetter. The truck stays cool riding around town or stopped, but when I'm running the ac stopped for a period of time, the temperature starts to climb. It never overheats, but does go above 210 substantially. The fans are pullers and I'm pretty sure the stock fan is a pusher. So I don't know if they would work together. Also, would it be beneficial to put the stock shroud back on? There is room to put both back on, just curious if this could help cool the truck back down in hot days when im running the ac. Pic for reference:

2011-06-23_14-16-29_750.gif
 

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ΜΟΛΩΝ ΛΑΒΕ
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Those fans as well as the stock fan both should be pullers. You actually would see a slight gain if you spaced those fans back a bit and made a custom shroud to take advantage of that 2-3" of open radiator core I can see to the left of the fans. What fans are those? What CFM?

90% of the time the electric fans will never match the cooling ability of the stock clutch fan setup at speeds above say 2500rpm, while the stock setup will never match the electric fans ability at idle.

If you can fit the shroud around those efans and fit the stock fan back on you could get the best of both worlds. Run the stock fan for maximum cooling, then add the electric fans to assist at idle. Although you would have more drag both on the engine from both the mechanical fan and the alternator.

Since both are pullers, they would assist each other much the same as most guys setup the stock puller along with an electric pusher on the other side of the radiator.

If I were you though I would pull the efans, throw the mechanical fan back on see how it does, and maybe throw on a pusher e fan on the condenser for added cooling with AC.
 

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Dukking Around
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Discussion Starter #3
The fans are Jegs dual 11's pulling 2760 cfm. I knew they were pullers, just wasn't sure as to what the stock clutch fan was, puller or pusher.

What fans are those? What CFM?
If I were you though I would pull the efans, throw the mechanical fan back on see how it does, and maybe throw on a pusher e fan on the condenser for added cooling with AC.
I can't do that. The reason that I put the e-fans on was because of the body lift, even with the shroud relocation brackets, the truck would overheat stopped. These fans have fixed all of my overheating problems, but with hotter days approaching, I just want to be prepared. Appreciate the help Garrett, I'm going to throw the shroud and fan back on right now.
 

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The fans are Jegs dual 11's pulling 2760 cfm. I knew they were pullers, just wasn't sure as to what the stock clutch fan was, puller or pusher.



I can't do that. The reason that I put the e-fans on was because of the body lift, even with the shroud relocation brackets, the truck would overheat stopped. These fans have fixed all of my overheating problems, but with hotter days approaching, I just want to be prepared. Appreciate the help Garrett, I'm going to throw the shroud and fan back on right now.
:eek: only 2760 CFM? That's alot of your problem, I think the LS1 fans are rated at just under 4000, and the 05 Efans are rated at just under 5000 cfm. Easiest bet would be throw the stock shroud back in and mount a 4000 CFM Ford Taurus fan in the shroud opening. I can see the issues with the gaps left behind by the body lift fan shroud spacers.

2760 is plenty for cooling a regular SBC, but not when you start running AC.

Stock fan is a puller for sure, unless your belts were on backwards and spinning it the wrong way. I have seen some offroad rock crawlers run a backwards fan to push hot air out of the engine compartment, works decent for slow speed and idle, but would bring the suck when driving down the road. Even then a regular puller fan and hood louvers would work better for an offroad rig.
 

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P.I.M.P. Trucks
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bigger efans.
 

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GMFS Senior Member
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:eek: only 2760 CFM? That's alot of your problem, I think the LS1 fans are rated at just under 4000, and the 05 Efans are rated at just under 5000 cfm. Easiest bet would be throw the stock shroud back in and mount a 4000 CFM Ford Taurus fan in the shroud opening. I can see the issues with the gaps left behind by the body lift fan shroud spacers.

2760 is plenty for cooling a regular SBC, but not when you start running AC.

Stock fan is a puller for sure, unless your belts were on backwards and spinning it the wrong way. I have seen some offroad rock crawlers run a backwards fan to push hot air out of the engine compartment, works decent for slow speed and idle, but would bring the suck when driving down the road. Even then a regular puller fan and hood louvers would work better for an offroad rig.
Bingo. That's the issue Brent. They simply don't move enough air.
 

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Dukking Around
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Discussion Starter #8
I can see the issues with the gaps left behind by the body lift fan shroud spacers.2760 is plenty for cooling a regular SBC, but not when you start running AC.Stock fan is a puller for sure, unless your belts were on backwards and spinning it the wrong way.
Appreciate all that dude. Yeah, the gaps from the body lift spacers were killing me, thats why I went with e-fans a while back. I just reinstalled the stock clutch fan and upper and lower shrouds with the spacers and it truly runs soooo much cooler. Never really thought about running both until today and just wanted to make sure the stock fan was a puller. I knew the 2760 was going to be a small number, but I'm not really a fan of junk yard shit and really liked the way these fans were basically plug and play. Of course I had to mount the thermostatic switch and run the two relays for each fan and a relay for the ac compressor, but that shits not really hard to do. Also, I figured with the build on the motor, to include new radiator and water pump, it would probably be a little more efficient than a stock one. The belt definitely wasn't on backwards, nor was the fan turning the wrong way, it has just been so long since it was on there I couldn't remember if it pushed or pulled. After letting it idle for ~30 minutes with the ac on, it never broke 210. And I swear the air in the cab is 10 degress cooler. Seems like with the two running together I should be good from here on out.

do you have room to mount some pusher efans on the front side of the radiator ? or put some more powerful fans in there
No. In front I'm running a B&M external trans cooler on the passenger side, and when I finish collecting parts the driver side will have an external oil cooler. As for larger fans on the inside, I would have to either pull everything I've got on there now off, and start over with a larger cfm set of fans, or just run it the way I set it up today. I'm going to leave it the way it is now because it's running like it should now that they're operating like Garrett stated in his first response.

bigger efans.
Read above.

Bingo. That's the issue Brent. They simply don't move enough air.
Works well now. It's taken some time to figure out how to properly set them up and still have everything working properly. I would have gone with a larger cfm setup if running the stock clutch fan and shroud with them didn't work, but it seems as if I'm done now with the cooling system. Maybe it'll get to the dyno this month...
 

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still doing good with this set up? i just started looking into running an efan on my truck due to these hot summer days and my ac sucks dick due to having the bl and i still have the shroud with the spacer brackets on there. just looking into which kit i should get
 

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Dukking Around
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Discussion Starter #11
Yeah, now that I'm running my stock fan and shroud with the dual 12's, it doesn't break 220 in 95° weather with the ac on. If I was to do it over though, I would have just gone with a larger cfm fan set so I wouldn't have to run the stock fan too. If you're going to do this, just get a set that pulls above 4000 cfm. As for the ac relay, I'm running a flex a lite relay that turns the fan on as soon as the ac button is pressed. If the kit you buy doesn't come with one, just buy the flex a lite relay kit, it's only like 20 bones. You will need it or you'll smoke your ac compressor pretty quick.
 

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Im trying to find out what fan clutch i need for for my 99 Z71 with 5.3
The one on the truck went bad. Autozone says they have a automatic fan clutch and manual one i dont know which one i need can anybody help?
 

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Im trying to find out what fan clutch i need for for my 99 Z71 with 5.3
The one on the truck went bad. Autozone says they have a automatic fan clutch and manual one i dont know which one i need can anybody help?
The "auto" "manual" application in that case has to do with whether you have the "auto" AC climate controls or just the normal manual controls inside. It simply activates the clutch at a different temperature. The clutch itself is not auto or manual, they are simply divided by thermal or non thermal. All fan clutch applications in our case would need to be thermal.
 

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TTG shawty
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efans dont pull near the cfm a stock clutch fan does. if your truck is running hot while idleing with the a/c on replace your clutch fan first and see if that doesnt help.
 

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efans dont pull near the cfm a stock clutch fan does. if your truck is running hot while idleing with the a/c on replace your clutch fan first and see if that doesnt help.
Welcome to 3 months ago, he did, it worked, all is well, some newbie dug up the thread to post an unrelated question.
 
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