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McMark
Is there a way to evaluate the potential maximum air flow that an oil cooler can support? The restriction of the fins must limit the amount of air that can be reasonably moved through the cooler. I'd like to be able to evaluate an oil cooler and see if fans would be able to move enough air. As always I'm looking for quantitative analysis information.

I'm hoping 900 CFM would hopefully be enough air for this cooler. (28"x3.5"x3.5")
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Aaron Cox
ahhh the hugely wide nascar oil coolers.....

lots of fans? where would you mount it?
McMark
I'm hoping to get something that will work with the stock holes in the front of the trunk and mount close to front of the trunk. That would leave most of the front trunk available. Eight 90mm, 120 CFM computer fans would fit perfectly. I'm just exploring what's possible instead of just going giant and cutting correspondingly giant holes in the trunk.

Besides that cooler I was looking at a pair of 14" coolers run in parallel. They are much taller (6" I believe) and would cool better. I just came across the 28" cooler tonight and it looks nice, but maybe a little too small.
McMark
Nuthin? No air flow research?
JmuRiz
I wouldn't think you'd need a fan, as long as it's vented out the bottom, like the GT (it didn't have a fan AFAIK).
Demick
Assumption: This is for a 4cyl car, and it is being used as an aux cooler and the engine still has it's stock cooler.

If my assumption is correct, I don't think you should need any fans. The only time you need the extra cooling is when you are moving - and since this is a front mounted cooler, you will get plenty of airflow under those conditions. You shouldn't need the extra cooling if you aren't moving.

Demick

P.S. you will be lucky to get 40CFM out of a 92mm muffin fan mounted to that cooler. More likely you will get 20-30CFM per fan.
McMark
It's for a six. Why would a fan rated at 120 CFM only give me 20-30 CFM?
ArtechnikA
QUOTE (McMark @ Aug 10 2005, 02:40 PM)
It's for a six. Why would a fan rated at 120 CFM only give me 20-30 CFM?

4, 6 - either way it's an aux cooler...

most little fans spec airflow in freestream air.
a little like saying your car will go 165mph because you can redline in 1st gear.
they are okay for ventilation - no big pressure drops or flow restrictions.

but you don't care what a fan will do sitting on your desk - you care what it'll do trying to shove air into a radiator. or pull air through a radiator. makes a difference, BTW.

i'm curious why you think you need it. are you dispensing with the engine-mounted cooler? are you running a 3,6 with no engine mounted cooler? 'cause otherwise the stock cooler does a fine job of dropping temps when there is no load (e.g.. - sitting in traffic). the only reason most 911's run fans is that they have AC and the additional operating load at idle causes heat rise.

at high roadspeeds, where "high" isn't actually that fast, the fans actually restrict flow because they can't move air at 50 mph...
Demick
Yep. What Rich said....

That cooler looks very restrictive (from an airflow point of view). Small muffin fans are great at enclosure ventilation, but lousy at pushing (or pulling) air through high pressure drop applications.

Demick
McMark
It's a 3.6 project and it'll have AC. The pressure issue makes sense. I've ordered a digital anemometer to try and get some air flow readings while driving. I haven't given up on trying to make a compact cooler setup.

Has anybody ever heard of an oil to freon cooler? Sincet the car will have AC, it would be cool to use the cooling power of freon to cool the oil.
ArtechnikA
QUOTE (McMark @ Aug 10 2005, 03:48 PM)
It's a 3.6 project and it'll have AC.

alrighty then - fans it is!

maybe you could use a big-ish squirrel-cage blower, with a rectangular opening and a round exit duct.
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