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PostPosted: October 6, 2016, 4:00 pm 
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Joined: July 18, 2009, 9:40 pm
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Location: Frankfort, KY
Well, now that I think about it, I might be able to fit the new fan behind the radiator if I'm careful about it. I got the 4 row radiator, which is roughly twice as thick. That required me to add about 1.5 inch out front. If I switch to the 2 row (probably better anyways) and add a 3000+cfm puller (compared to my current 1250cfm or something ridiculous), That might do well. I won't be able to fit a puller shroud though easily. Will that completely defeat the purpose? Current "1250" cfm fan has a shroud.


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PostPosted: October 6, 2016, 4:06 pm 
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Joined: July 18, 2009, 9:40 pm
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Location: Frankfort, KY
I'm considering this thing (which definitely is very bulky if its a pusher). My only worry is that it is doesn't have a shroud on it as is.
https://www.summitracing.com/parts/prm-19112


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PostPosted: October 6, 2016, 8:44 pm 
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eh3civic wrote:
... I won't be able to fit a puller shroud though easily. Will that completely defeat the purpose? Current "1250" cfm fan has a shroud.

As mentioned elsewhere (maybe in this thread) the shroud only serves a useful purpose while the car is stopped, forcing all the air passing through the radiator core to be pulled or pushed through by the fan. At speed, the same shroud actually prevents the radiator from working to its full capacity and will make an already marginal system run warmer. My brother runs no fan at all on his LS3-powered Stalker and it works for him because he doesn't drive in heavy traffic. If he knows he's going to sit a while, he turns the engine off.

Have you already spent time working on getting the air exiting the radiator to flow smoothly into low pressure areas?

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PostPosted: October 7, 2016, 9:01 am 
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Im not sure that shroud logic is sound.

I believe the radiator core will offer more resistance to flow than the opening in the shroud, unless the fan is very small.
One could always employ flaps to act as check valves and allow flow in positive pressure.
The cooling system should not be designed to be close to the edge of inadequacy in normal operation.
A compromise must be made in favor of some cooling overkill, over weight.
It is better to be a little heavy than to have a steamer!
And any cam in head motor, warping the head is a financial disaster.

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PostPosted: October 7, 2016, 9:04 pm 
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Joined: January 28, 2016, 7:59 pm
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Location: Omaha, Nebraska
I think I have a solution for the overheating, though you may not like the idea.

Remove the bottom of the nose (or at least most of it) and replace it with a few light pieces that hold it together, maybe a grill that doesn't impede air flow too much. Then tip the radiator forward so that the top fits into the very top leading edge of the nose and the bottom hits the back of the recently cut and open bottom of the nose. If still more cooling is needed you can put a kind of splitter on the bottom of the nose that catches air that would otherwise have gone under the car and feeds it into the radiator. Then put a puller fan on the back of the radiator and you should be able to cool the engine with no trouble.

Looking at how the nose sits on your car, it seems like there would be quite a lot of air going under the nose and pressing up on the underside when you're at speed. If you can get that high-pressure air directed up through the radiator and out of the back of the engine bay you'll likely solve the cooling problem, and as a bonus reduce lift on the front of the car.

-Graveyard

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PostPosted: October 9, 2016, 2:30 pm 
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Joined: July 18, 2009, 9:40 pm
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Location: Frankfort, KY
Update: I made a lot of stuff yesterday and now it cools at speed (running at about 190 on cool day on highway). I was able to take the first 20+ mile drive. Very fun car. It still won't cool while idling (unless it does, just a bit hotter). I'm probably going to test my temp gauge/sender at some point. I've got a sealed radiator (almost sealed, still have about 1/2inch on top and bottom of the incoming air). Also worked up an airtight shroud on the new 3300cfm puller fan and switched back to my old 2 row radiator. New tank is aerating fine it seems.


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PostPosted: October 9, 2016, 7:57 pm 
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190 on the road should be fine, there's a pretty good chance that's what your thermostat is set for, unless you bought a colder one. Where does your fan come on? If you can adjust that, maybe set it so your fan comes on just above 190 and see if it cycles when idling. If it does cycle, the fan is moving enough air. Might want to repeat on a hot day though before you get stuck in traffic somewhere. My car runs right around 190 when driving, then idles around 203-205.
Kristian

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PostPosted: October 10, 2016, 1:01 am 
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Joined: July 18, 2009, 9:40 pm
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Location: Frankfort, KY
I'm 90% sure it's a 160 degree milidon thermostat, but in trading it was fully open by 180. The fan is just on a switch, and that was running constantly once up to temp. Going to add a temp switch to automatically turn it on soon.


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PostPosted: October 18, 2016, 11:51 pm 
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Did we get to some good news here or are you still struggling?
:cheers:

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PostPosted: October 21, 2016, 3:01 pm 
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Joined: July 18, 2009, 9:40 pm
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Location: Frankfort, KY
Thanks for checking back in, but I'm homeless right now and the car is stored somewhere else (but I am going to be having a really nice garage soon!). That first 20 mile drive was literally me dropping it off at the garage to store it. I'll update just as soon as I have an update though!


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PostPosted: April 2, 2017, 8:45 pm 
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Joined: July 18, 2009, 9:40 pm
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Location: Frankfort, KY
It has been a long time since I've checked in (work, moving, etc), but I still haven't worked out the issue. Running a 4 core half-size civic radiator (with pusher and puller fans on it, 2950 cfm each just to check if I could cool it at idle), and 2 heater cores with fan. Going to add another full size radiator into the back of the car next unless there is a better idea. Changed the thermostat, adding the expansion tank, etc. Temp gauge is reading as expected. The car will sit much longer without overheating, but once again the 4-core had no difference in cooling. It is a cheapy ebay 4-core, so that might be the reason.

I think I'll first mess with the pulley ratio. Right now I think It is off, and on the wrong side of cooling.


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PostPosted: April 2, 2017, 11:19 pm 
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Joined: March 30, 2011, 7:18 am
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Location: central Arkansas
Ford has two styles of water pump - the early 289/302 with a proper scroll and closely-fitted impeller, which can squirt coolant halfway across the street at idle, and the 5.0-style "paddle in a box," which is pretty wimpy at idle and low speed. A few 5.0 applications had scroll-type pumps, but they were typically trucks.

You can buy an aftermarket scroll pump, but it's usually cheaper to fit an electric booster pump in a lower radiator hose.

Also, the small block Ford is prone to air pockets in the water pump and cylinder heads, particularly if the engine is sitting level in the chassis. It can take several operating cycles to entrain all the air and bleed it through the overflow tank. Some V6 engines have brass fittings to bleed air when the cooling system is serviced; mounting one on the water pump and at the back corners of the intake make it easy to bleed. I went with AN fittings and -4 hose to a surge tank, Carroll Smith style, when I did my RX7, but that's overkill unless you have the stuff laying around.


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PostPosted: April 2, 2017, 11:28 pm 
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Location: central Arkansas
eh3civic wrote:
Changing my focus to the fan. My current fan is woefully inadequate I think.


I've sworn off aftermarket fans, even if they're major brand names, after noticing that even a crusty junkyard OEM fan blows a *lot* more air than any aftermarket fan I've played with. I pulled a couple of fans off a Camaro that would probably have worked to make a hovercraft.


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PostPosted: April 17, 2017, 7:00 pm 
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Joined: July 18, 2009, 9:40 pm
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Location: Frankfort, KY
So, just switched back to a single puller and went with a "Mishimoto MMRAD-CIV-92X X Line Performance Aluminum Radiator" which is a 3 row dual pass radiator. I'm now better off than I've been, but it still isn't quite acceptable. If the temp gets high enough, the car can't cool itself (without being at hwy speeds). I literally don't know what to do now except for adding more coolant volume possible (I think I have less than 2 gallons total for a 450hp engine). The "easy" method would be to run another race radiator in the back of the car and route coolant lines all the way back. I'm not positive that I have room. I had a 4 core radiator (cheapy from ebay) that didn't do well at all, but perhaps I could have a "really" thick radiator up front instead of running 1 in front and 1 in back?

Setup as it stands:
Surge tank
added in 2 heatercores for testing, seem to flow fine
Mishimoto MMRAD-CIV-92X X Line Performance Aluminum Radiator, 3 row, dual pass
2900 CFM fan with sealed shroud
radiator ducting for at speed.
Standard sized drive pulley, and overdriven water pump pulley.


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PostPosted: May 21, 2017, 4:41 pm 
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Joined: July 18, 2009, 9:40 pm
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Location: Frankfort, KY
Any thoughts on what might cause this? After warming up the car (and burping it with this no-spill funnel method), I shut the car off. At this point it is at about 210F when I shut it off. The coolant then rises pretty dramatically with what seems like air bubbles, but you can judge from the video below. Beware of moderately loud audio at the beginning. My thoughts lead me to bad head gasket although while it is running I don't have any bubbles rising after burping it the first time.

https://goo.gl/photos/iFPLY9Zq8wCK8VVM6


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