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Old 04-21-2001, 12:17 AM   #1
BongMan
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Question "Do Air Filters Really make Power"?

Is there any Cone filter that makes better power, or perhaps flow than Another? I have a K&N filter that only draws air from around it. But I've seen the Apexi and the Tenzo R filters with multiple points of entry. Would this make the flow rate better or worse because of conflicting currents?
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Old 04-20-2001, 02:48 PM   #2
Skylab
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Umm, a filter cannot make power. BECAUSE, what would happen if you had no air filter? It would suck in even more air. Put the filter on, and it is robbing power. What filter robs the least amount of power from the engine?

Skylab
*just a theory*
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Old 04-20-2001, 03:10 PM   #3
RS2001
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......................
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Old 04-20-2001, 03:26 PM   #4
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Going by your theory then, the stock intake robs power from the engine, and when you put on say a Rallispec intake, then you are robbing less power from the engine? I'm not trying to flame you, just giving another example of your theory.

Jim
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Old 04-20-2001, 03:37 PM   #5
Chav
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Yeah, intake and exhaust dont make power. They free up power. Just like pulleys do.

-Chav
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Old 04-20-2001, 03:38 PM   #6
Retsyn
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That's been my experience. Got Larry's CAI and an amsoil filter. It's MUCH better. The car just goes. It also seems to have cured my hesitation at 4000RPMs problem. It's also improved my fuel economy (except when I hop on it ).
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Old 04-20-2001, 04:45 PM   #7
Kevin Thomas
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My theory (or fact for this matter):

Power is energy. Energy can not be created nor destroyed, only changed in form. So in effect, you can never make (or create) more power by doing ANYTHING to your car. It's all a hallucination. A fantasy of sorts.

On a more serious note, I believe the Larry Ganz intake has the best power-per-dollar ratio amongst the intakes out there based on a lot of this clubs members.



[This message has been edited by Kevin Thomas (edited April 20, 2001).]
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Old 04-20-2001, 04:50 PM   #8
Skylab
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*...more theory shiz...*


By not having a turbo on my engine, it's being robbed of power.

Skylab
*what was the question?*
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Old 04-20-2001, 09:59 PM   #9
Chav
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Nooo. Ok Let me elaborate (sp). By adding an intake and exhaust you are allowing the engine to breath freely. Ok we agree on that. Now less energy from the combustion is used to push or pull the air in and exhaust out. Now when u add a turbo you are increasing the power of the combustion so I would say you are "creating" power. This power was not there before.

-Chav
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Old 04-20-2001, 11:34 PM   #10
XT6Wagon
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Thank you chav, now please go "free" yourself from the shortbus.

Intakes and exausts can and DO "create" power. By this I mean that the engine has more HP than would be present if they were not installed. Factory hardware included. How much power would you have if you simply took off the headders?? Very little. The intake is also a good example, in that if you put on a 30" TB and plenum w/o any filter its likely to make less power than a properly designed intake WITH filter.

More is NOT better in engine design, there is a happy medium for every application.
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Old 04-21-2001, 09:57 AM   #11
Chav
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Man u dont have to be an a$$ about it.

-Chav
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Old 04-21-2001, 02:52 PM   #12
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wow... 10 replies and still no one has answered Bongman's question...
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Old 04-21-2001, 07:43 PM   #13
JNaubur
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I'm not going to answer his question either. But hopefully I will demonstrate this 'free up power vs. create power' idea.

You cannot 'create' energy. There is potential energy and kinetic energy. Gasoline has much much more potential energy than any internal combustion engine could ever use. You're lucky to get 20% efficiency out of an engine. Adding turbo or s/c or intakes or even new plugs just makes your engine more efficient at using the gas. So all any mod ever does is use more of the energy that gasoline has stored away.

That being said, if my car makes 150 HP, I add a new CAI and now I have 155 HP (just go with me here) it feels to me like I just made 5 extra HP. And if I race your 150 HP car, I'll win (by a little). It's just semantics. Sure I didn't 'make' more energy, but I sure made my car faster.

Didn't mean to come across as a lecture, but my old science teacher would be mad if I didn't point this out.

Whew, I hate typing in that little box.

JNaubur

PS I'm no scientist but I remember the theory.
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Old 04-21-2001, 08:35 PM   #14
WRC666
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A high performance filter allows more air to enter the motor, thus giving more O2. The MAF or its equivalent reads more air and adds more fuel to the mix to stay within the preset limits for air/gas mix. More gas/air = more power. And a K&N filter allows a smoother airflow in the intake. Turbulences irritate the sensor and slow the airflow.
The reasons why the stock intake is so restricted is noise and to have longer service intervals for the filter. A high performance filter is also more "open", which can be a bad thing in very dirty environments. Thats why the K&N's are oiled, to trapp dirt. At least to my knowledge( which is limited, of course).
Trade-off for a cone filter is noise. Too bad...
666
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Old 04-22-2001, 04:20 AM   #15
Keiho
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Best flowing filters I know of.

Apex'i
Blitz
Greddy
Sard
HKS

I think they're ranked something like that...actually, the Blitz probably outflows the Apex'i unit, but the Apex'i filters much better.
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Old 04-22-2001, 02:05 PM   #16
tonytiger
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Has anyone has a dyno with the filter and without? Or has anyone ever even saw one? If you take a look at a power or torque curve it's best if the whole rpm range is high. Even though the air filter wouldn't rise the peak level, could it be possible to see gains in overall rpm performance?
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Old 04-22-2001, 07:43 PM   #17
Midwayman
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To answer the question, yes a filter will help with power on the high end. Cone, replacement panel, whatever. Both oiled cloth and foam are better than stock. That said, the filter really makes a minimal difference. I bet if you had a CAI that used the panel filter (ganzflow for example) that if somebody swapped the filters back and forth without you knowing the only difference you'd notice is noise. Dynos will show 1-3 hp. Not exactly alot. However the more 'tuned' you engine is the more the filter makes a difference. (IE adding heads, cams, TB, headers etc will change the effect of the filter)

And as to the whole the power is always there argument.... It is allowing you to make more power. More air means more fuel can be burnt. That makes more power. Nothing magical about it.
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Old 04-23-2001, 09:41 AM   #18
BongMan
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Thumbs up

Thanks for the responces. I think i'm gonna look at the apexi blitz greddy filters. I remeber looking at an import tuner where they dyno'ed a apexi cone on a mr2 and it killed torque. Maybe i should get a my 98 box. Hmmm. We'll see what happens.

also i think it's funny that i got a lot of responces about how a filter doesn't make power but i stated in my opening post "power or Flow." Futhermore i put quotations around the topic just to avoid the engines make power not a (place not enternal engine mod here).

Question, would the first air box on a my 98 or 99 lower the amount of torque loss when placed on the end of a Tubular intake such as a weapon R? Has anyone tried this?
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Old 04-23-2001, 10:31 AM   #19
tomas
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I also installed Larry's CAI and I don't care how much HP was added (Can you tell a 5HP difference anyway? I don't know...) For me, I enjoy the faster throttle response. I don't believe my car goes any faster (whatever faster means) but it sure makes a difference in getting there.
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Old 04-24-2001, 10:22 AM   #20
Midwayman
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In the Ganz flow, the tubing is the cause of the power gain, not the filter (for the most part)
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