Question on cone air filtering.
#16
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The only reason you loose power is because of the hotter air getting into the intake.
If he puts a heatshield on it and a scoop he shouldnt see any loss he might even see a small gain.
If he puts a heatshield on it and a scoop he shouldnt see any loss he might even see a small gain.
#17
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OK, here is my 2 cents.
I ran an MSDS cone filter adaptor for the last 4 years. It is one of the better designed cone adaptors out there that I have seen because it is actually slightly contoured to funnel air rather than some of the cheap "hole punched in the bottom of a tin can" hunks of **** on the market which tumble the intake air. I thought I noticed some gain when I first installed it, but it was likely just fantasy caused by the more rorty sound of the open element intake. I kept reading all of the criticism from folks who had never run or tested a cone agains stock claiming that you lose power because the cone setup sucks hot air out of the engine compartment. Well, I can tell you this is not the case. When the car is in motion most of the hot air is sucked out of the engine compartment anyway, so the cone setup does not suck it into the engine. I know this because I measured the temp with a remote temperature probe earlier this summer and found the under hood temp dropped quite a bit once the car got rolling. When the car is idling in traffic, the under hood temp does go up quite a bit though, so idling in traffic/stop and go can be a bit of a problem. In fact the under hood temp while sitting in traffic went up as much as 70 degrees fahrenheit, though it dropped down fairly quickly once the car got back up to speed for a period of time.
Anyway, just to be fair I reinstalled a stock setup to do some temp checks on the inside of the airbox when sitting in traffic. But you know what happened? The first time I started my car after reinstalling a complete, stock airbox setup I noticed that the car had better throttle response. I mean within moments of starting the car and starting to drive around. My point is that the under hood temp was still at or near ambient, so hot air wasn't even a factor at that point. My conclusion is that cone air filters have a negative impact on performance, but hot air has NOTHING to do with it. Porsche engineers really did do their homework on the design of the intake. The shape of the snorkel that runs from the fender to the airbox is well thought out as is the shape of the airbox itself. all of it contributed to better intake velocity for better cylinder filling. You really, from my experience, screw that up when you switch to a cone filter setup.
I ran an MSDS cone filter adaptor for the last 4 years. It is one of the better designed cone adaptors out there that I have seen because it is actually slightly contoured to funnel air rather than some of the cheap "hole punched in the bottom of a tin can" hunks of **** on the market which tumble the intake air. I thought I noticed some gain when I first installed it, but it was likely just fantasy caused by the more rorty sound of the open element intake. I kept reading all of the criticism from folks who had never run or tested a cone agains stock claiming that you lose power because the cone setup sucks hot air out of the engine compartment. Well, I can tell you this is not the case. When the car is in motion most of the hot air is sucked out of the engine compartment anyway, so the cone setup does not suck it into the engine. I know this because I measured the temp with a remote temperature probe earlier this summer and found the under hood temp dropped quite a bit once the car got rolling. When the car is idling in traffic, the under hood temp does go up quite a bit though, so idling in traffic/stop and go can be a bit of a problem. In fact the under hood temp while sitting in traffic went up as much as 70 degrees fahrenheit, though it dropped down fairly quickly once the car got back up to speed for a period of time.
Anyway, just to be fair I reinstalled a stock setup to do some temp checks on the inside of the airbox when sitting in traffic. But you know what happened? The first time I started my car after reinstalling a complete, stock airbox setup I noticed that the car had better throttle response. I mean within moments of starting the car and starting to drive around. My point is that the under hood temp was still at or near ambient, so hot air wasn't even a factor at that point. My conclusion is that cone air filters have a negative impact on performance, but hot air has NOTHING to do with it. Porsche engineers really did do their homework on the design of the intake. The shape of the snorkel that runs from the fender to the airbox is well thought out as is the shape of the airbox itself. all of it contributed to better intake velocity for better cylinder filling. You really, from my experience, screw that up when you switch to a cone filter setup.
Last edited by Manning; 09-09-2004 at 10:44 PM.
#18
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What about cutting the top of the air filter box and then installing the hood scoop over it?
Would this be the best of both worlds or just take what's bad of both set ups?
Would this be the best of both worlds or just take what's bad of both set ups?
#19
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How will you keep water from getting sucked into the intake if you get caught out in the rain? May not amount to much, but who knows. The hood scoop on the 924 Carrera GT was over the intercooler, not the intake.
Edit I realize some old muscle cars had scoops that pretty much fed straight into the carbs, but did they have some way to facilitate the evacuation of water in a downpour?
Edit I realize some old muscle cars had scoops that pretty much fed straight into the carbs, but did they have some way to facilitate the evacuation of water in a downpour?
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Originally Posted by Manning
How will you keep water from getting sucked into the intake if you get caught out in the rain? May not amount to much, but who knows. The hood scoop on the 924 Carrera GT was over the intercooler, not the intake.
1) Place a foam sponge behind the opening as to soak up all the water.
2) Place a foam sponge "ring" around the opening. The water's capilary force will keep it from "flying" into the scoop. It will try to drip in, were the sponge will take it.
3) Make a "plug" for when it's raining.
Who said you can't learn anything from ricers. He did #2 for his NACA duct.
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Originally Posted by Manning
He did #2 for his NACA or it looked like #2 ![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
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He set up a NACA duct but was worried that this type of set up would create a cascade over his filter. He made a sponge lip under the lower part of the duct. He made sure that the sponge was not placed over the cone it'self so if it dripped, the water would fall before the cone. By placing a grill in the openning you could not see the foam.
#23
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Originally Posted by Sam Lin
Standing water to a few inches above the bottom belt will do it - the belts fling the water upwards and it gets pulled through that pipe into the engine - do a search, I didn't know about it until reading about it on here - as you mentioned, I certainly don't worry much about it in AZ.
Sam
Sam
For all the miles and all the extreme conditions I have put 944s through, the strange problems some people whose cars always seem to be broken have that I have never encountered never cease to amaze me. And 95% of the time I find out later that there is something else missing, broken, or (most often) modified on their car that contributed to the cause.
![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
Some of the things I have read about people doing to their cars on here make me cringe, like cutting a hole in the hood to get fresh air for a garbage air filter. It's funny how so many high school and college kids seem to think that for a few bucks they can outdo years of development by some of the world's best engineers.
![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
Here's a novel thought about cone air filters: Perhaps, just maybe, the engineers at Porsche calculated the maximum volume of air that the engine could possibly draw, taking into account things like horsepower and RPMs, vacuum, air density, inner diameter and length of the intake components (like the throttle body), etc., and then examined the resistance to air flow of a particular type of paper element, and then maybe calculated how large that element might have to be to not (or at least minimally) hamper the air flow. Maybe (I'm just guessing), then they thought of finding a place in the engine compartment that was as far as possible from the exhaust manifold, and perhaps near the front of the engine compartment where the exterior would be getting hit by the most cool air. Maybe a certain kind of plastic was chosen because of its durability, resistance to heat and elements, and for its insulating properties (both noise and heat), and maybe the choice of putting the intake hole inside the fender was because of all of the cool, fresh air being circulated inside with great force. I don't know. I honestly have no idea, but looking at the size of the air filter, the materials, the placement of the components, etc., I might guess that they probably had a GOOD reason for that, and probably knew what they were doing. Cone air filters might work great on a Saturn, but if Porsche could have squeezed another ounce of power without compromising reliability, they would have. This is a Porsche, not a Chevy Cavalier or Honda Civic.
my .02 and then some...
#24
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My mechanic had a couple towed in, here in Maryand. They locked up from driving through standing water after we had a pretty heavy rain. The intake from the fender well sucked the water straight up the intake. He told me it was not that uncommon. Be carefull around standing water. He also refered to the drivers as idiots.....as in, how could you not know that.
#25
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Originally Posted by Tony K
Two times I drove my 83 through water deep enough to break the blades off of the electric fans (1 flood, 1 rally). You're gonna have to drive through water deep enough to submerge the intake inside of the front fender to get what you are talking about. Seriously, how much water do you think the balance shaft can cary up to that little hose, that won't get absorbed by the air filter? Maybe it will take in more water with the timing belt covers broken or rubber plugs missing? What you are describing sounds like a problem that people who mickey-mouse their cars have.
For all the miles and all the extreme conditions I have put 944s through, the strange problems some people whose cars always seem to be broken have that I have never encountered never cease to amaze me. And 95% of the time I find out later that there is something else missing, broken, or (most often) modified on their car that contributed to the cause.
Some of the things I have read about people doing to their cars on here make me cringe, like cutting a hole in the hood to get fresh air for a garbage air filter. It's funny how so many high school and college kids seem to think that for a few bucks they can outdo years of development by some of the world's best engineers.![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
Here's a novel thought about cone air filters: Perhaps, just maybe, the engineers at Porsche calculated the maximum volume of air that the engine could possibly draw, taking into account things like horsepower and RPMs, vacuum, air density, inner diameter and length of the intake components (like the throttle body), etc., and then examined the resistance to air flow of a particular type of paper element, and then maybe calculated how large that element might have to be to not (or at least minimally) hamper the air flow. Maybe (I'm just guessing), then they thought of finding a place in the engine compartment that was as far as possible from the exhaust manifold, and perhaps near the front of the engine compartment where the exterior would be getting hit by the most cool air. Maybe a certain kind of plastic was chosen because of its durability, resistance to heat and elements, and for its insulating properties (both noise and heat), and maybe the choice of putting the intake hole inside the fender was because of all of the cool, fresh air being circulated inside with great force. I don't know. I honestly have no idea, but looking at the size of the air filter, the materials, the placement of the components, etc., I might guess that they probably had a GOOD reason for that, and probably knew what they were doing. Cone air filters might work great on a Saturn, but if Porsche could have squeezed another ounce of power without compromising reliability, they would have. This is a Porsche, not a Chevy Cavalier or Honda Civic.
my .02 and then some...
For all the miles and all the extreme conditions I have put 944s through, the strange problems some people whose cars always seem to be broken have that I have never encountered never cease to amaze me. And 95% of the time I find out later that there is something else missing, broken, or (most often) modified on their car that contributed to the cause.
![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
Some of the things I have read about people doing to their cars on here make me cringe, like cutting a hole in the hood to get fresh air for a garbage air filter. It's funny how so many high school and college kids seem to think that for a few bucks they can outdo years of development by some of the world's best engineers.
![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
Here's a novel thought about cone air filters: Perhaps, just maybe, the engineers at Porsche calculated the maximum volume of air that the engine could possibly draw, taking into account things like horsepower and RPMs, vacuum, air density, inner diameter and length of the intake components (like the throttle body), etc., and then examined the resistance to air flow of a particular type of paper element, and then maybe calculated how large that element might have to be to not (or at least minimally) hamper the air flow. Maybe (I'm just guessing), then they thought of finding a place in the engine compartment that was as far as possible from the exhaust manifold, and perhaps near the front of the engine compartment where the exterior would be getting hit by the most cool air. Maybe a certain kind of plastic was chosen because of its durability, resistance to heat and elements, and for its insulating properties (both noise and heat), and maybe the choice of putting the intake hole inside the fender was because of all of the cool, fresh air being circulated inside with great force. I don't know. I honestly have no idea, but looking at the size of the air filter, the materials, the placement of the components, etc., I might guess that they probably had a GOOD reason for that, and probably knew what they were doing. Cone air filters might work great on a Saturn, but if Porsche could have squeezed another ounce of power without compromising reliability, they would have. This is a Porsche, not a Chevy Cavalier or Honda Civic.
my .02 and then some...
I do not agree that Porsche's engineers got everything perfect on these cars though. If they had you would never read about oil and coolant mixing or sunroof adjustment issues among other things.
#26
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Michael, yes, I was implying/taking as a given what you said in the first paragraph. And, of course, no car is perfect.
As for things like the oil cooler seals and sunroof, they are on a par with any other type of car in terms of longevity, as far as I can tell. I had two 944s with working power sunroof in the last couple of years - an 85.5 with 95k miles, garage kept, and an 84 with 70k miles but spent a lot of time outdoors in the Florida elements. From what I can tell, broken power sunroofs (and other accessories) are common on all older cars.
Oil cooler seals seems to be a 100k mile/17-year repair on average from what I've seen - what more can you expect?
Cheers,
As for things like the oil cooler seals and sunroof, they are on a par with any other type of car in terms of longevity, as far as I can tell. I had two 944s with working power sunroof in the last couple of years - an 85.5 with 95k miles, garage kept, and an 84 with 70k miles but spent a lot of time outdoors in the Florida elements. From what I can tell, broken power sunroofs (and other accessories) are common on all older cars.
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Cheers,
#27
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IF anyone has a stock air box that will fit on an '84 (I think they are all the same, but I'm not sure) and they want to get rid of it, please PM me.
i saw this one on ebay, but don't know if it'll fit - it's a bad picture and it's hard to see it.Will someone let me know if they are all the same?
http://cgi.ebay.com/ebaymotors/ws/eB...category=38634
i saw this one on ebay, but don't know if it'll fit - it's a bad picture and it's hard to see it.Will someone let me know if they are all the same?
http://cgi.ebay.com/ebaymotors/ws/eB...category=38634
#29
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Originally Posted by RMills944
IF anyone has a stock air box that will fit on an '84 (I think they are all the same, but I'm not sure) and they want to get rid of it, please PM me.
i saw this one on ebay, but don't know if it'll fit - it's a bad picture and it's hard to see it.Will someone let me know if they are all the same?
http://cgi.ebay.com/ebaymotors/ws/eB...category=38634
i saw this one on ebay, but don't know if it'll fit - it's a bad picture and it's hard to see it.Will someone let me know if they are all the same?
http://cgi.ebay.com/ebaymotors/ws/eB...category=38634
That photo looks like it's just the snorkel and airbox cover(top). I can't see the lower airbox case at all.