temperature of the air for cone filter.

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Old 06-29-2001, 06:21 AM
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Default temperature of the air for cone filter.

As I mentioned before, I consider installing the cone air filter. The problem is the OEM filter gets air from outside. The cone filter gets if from under the hood. If the under the hood air is much hotter, it will make it less condense and will reduce power of the engine. Simple calculations gives, that every degree Farangate (? spelling) will reduce amount of molecules by ~1/600. This should reduce power of the engine by 0.17%. For the 174hp engine every degree F will reduce power by 0.29hp.

Ok. So I put my Radio Shack thermometer in the engine compartment next to the place, where the cone filter would suck the air. The display is attached on the long wire, so I can keep right in front of me. The outside temperature, measured by the same thermometer is 82F. I mostly drove on the highway and found, that if I will keep my speed over 50mph, the temperature inside never will go above 85F. If I would slowdown up to 30mph, the temperature will go up to 88F - still not a big deal. But if I will stop on the toll plaza - it will jump up to 110F almost instantly. If I will stand for a two minutes with idling engine, temperature will become 134F!!!. But as soon, as you start moving, temperature will drop.

So the results of the tests are: during the driving (let us say above 30mph) cone filter would suck cool air, coming from the outside. If you will slowdown or stop for long time (more then a minute), air will heat up from the engine and engine with cone filter will loose ~8% of the power. It will regain this power very soon after you will pick up the speed. We still do not know, how much heat air picks up, when it travels inside of the intake pipes. But because, it does to the certain extent, we should expect less difference in the air temperature for cone and OEM filters.

So as a result I would favor the cone filter. And as we know from people, who installed the filter it does help.
Old 06-29-2001, 07:55 AM
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Good post...this needed to be checked!!
Old 06-29-2001, 08:36 AM
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You lost me after "Farangate" ;-).
Old 06-29-2001, 09:35 AM
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Default If I would use Kelvins, Would it be easier to read?

The idea of my message was: The cone filter sucks air from the engine compartment. The air warmer and it reduces power of the engine. But still it makes sence to install cone filter.

Sorry for my English...
Old 06-29-2001, 09:52 AM
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Default Re: If I would use Kelvins, Would it be easier to read?

I'm still not sure that I understand. Wouldn't the outside air always be cooler than the air under the hood? Therefore would it not be better to have the OE filter that gets its air from the outside rather than the cone filter that is getting the warmer air from under the hood?
Old 06-29-2001, 10:30 AM
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Only if the OEM set-up could flow as much air as the cone!!!
Old 06-29-2001, 10:42 AM
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Default Re: If I would use Kelvins, Would it be easier to read?

I thought so. But I have put thermometer under the hood and found, that during the driving there is enought airflow to keep the temperature under the hood almost the same, as outside. If you will stop or drive in slow traffic, air will get hotter. I got 134F after two minutes of the idling. According to the calculations it should reduce power on 8% or less.

But again, the cone filter sucks more air and gives your 8% increase.

I also afraid, that if I will put cone filter and drive in the deep pudle, water will get up to the cooling fan. Fan will spray water all around the compartment and it will get into the cone filter.
I will wrap dry towel and drive into the lake to test it...
just kidding.
Old 06-29-2001, 12:27 PM
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Default The basic gist of it is, at highway speeds, the hot air doesn't just sit around under the hood.

It's always circulating cooler air in, so you really are getting more air in than the OEM that's the same temp as ambient. Makes sense when you think about it.
Old 06-29-2001, 10:55 PM
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Default It would be interesting to see...

how different underhood intake temps would be if you added a heat shield to the one side? You should try that too...

Steve Ankney
88 5000
Holland, MI
Old 06-30-2001, 06:45 AM
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Default MIT Grad?

How about using those resources and come up with a good, functional heat shield!


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