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Old 09-01-2008, 11:29 AM   #21
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And here I am thinking of removing 1 fan from each of my cars because I don't need them. I don't have AC on either though.

I'm a strong advocate of the stock fans too. Something about a $20 ebay fan doesn't instill confidence. If you are having trouble fitting the stock fans with a thicker radiator and aftermarket sway bar it's nothing a lil dremeling won't fix. Just be sensible and leave enough support so the fan doesn't break free and eat the radiator.

What we need is someone to do some testing with temp probes before and after the radiator, in the radiator hoses. This way we can get a efficiency rating for the radiator with X fans with and without shroud. Then swap fans and test again.

It's been my experience that the car will run cooler at 4k rpm in 4th then it will in 5th at 4k. As someone stated earlier it's gotta be buildup of pressure at the front end which just diverts air around the mouth instead of through. That being said, since I've installed the Mishimoto radiator(and I've rerouted the heatercore to go back to the mixing manifold as stock did) my car is never above 196 while driving. I have my fans set to come on at 205 and they never do unless I'm idling a while. Once the stock fans(both) come on the temp gets kicked right back down below 200.

Mishimoto radiator, stock fans wired in parallel modified to fit with 26mm front sway, shrouding from the front air dam to the radiator along the bottom only(nothing up the sides like johndoe), no bellypan after the radiator, 18x12x3" core FMIC blocking the radiator along with some small projector lights, stock upper radiator cowl cover in place. 1/3 coolant, 2/3 distilled water.
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Old 09-01-2008, 12:24 PM   #22
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Originally Posted by Ben View Post
Bruce, make sure the fans' blades are set to pull and not push.
That was another member, not to be named in the interest of embarrassment

They are rotating correctly and both on together(Jumped to stay on in diagnostic box)
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Old 09-01-2008, 12:35 PM   #23
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I don't think wiring the fans to stay on constantly is a good thing. The fans are a resistance while higher speed air is trying to move past them as is. With the fans on it'll create a wall of slower moving air.

I was kinda wondering how many people run without the bellypan. I haven't for a good long time. Never had any coolant problems. I know I do eventually want to build a new one. Need to get the sheet metal for it first.
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Old 09-01-2008, 12:56 PM   #24
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I have used ebay fans on 3 different cars of mine and have been pretty satisfied. Doesn't mean they'll last forever, but at least they work in pairs so if one fails you still have another. I've had two 10" ones on my 86 Trooper II for a couple years. They've seen a hard life. Idling for hours, once for 24 hours, mud riding, water, dust, been completely submerged in water and mud several ties, etc. They're still kicking. For the 60 I paid for them, I'm happy. I hope the ebay 12's I bought are as good as these have been.

Now I agree with Brain that the fans are not the best and overrated. My 12's are rated at 1400 CFM. Maybe at 16.024 volts and free air. But put a restriction in front of them (radiator), and I'm sure that number drops A LOT. I'm sure a pair of Spals or other fans with stronger motors would be better. But they cost more.

I'm also suspicious that the needed mods for adequate cooling are different between NA's and NB's. Seems all the NB guys don't need new ducting in the front where most NA guys seem to. My car never overheats at speed. Only at idle conditions as described earlier.
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