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Title says it all lol. I don't drive hard (most of the time) and I'm more concerned about more mpg and efficiency than power. I've heard a lot of mixed things about which one actually DOES increase mileage. So I'd kinda like to settle it now since payday is coming up soon;) I'd like facts, instead of "what you heard or think you know" thanks guys!!
 

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Drop in filter would be your best bet in MPG increase. Lots of people think that a CAI would do it, but you have to consider that your airbox is basically a CAI, it pulls airflow into your engine. Lots of people will argue that its restrictive, but you have to ask yourself, "Did I increase the size of my intake valves or are they stock?". Engine design engineers design todays cars perfectly for MPG. Just the right amount of air, fuel, and exhaust for best volumetric efficiency. Manufacturers will argue against K&N cause of 3rd party reasons.
 

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Levee
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Drop in filter would be your best bet in MPG increase. Lots of people think that a CAI would do it, but you have to consider that your airbox is basically a CAI, it pulls airflow into your engine. Lots of people will argue that its restrictive, but you have to ask yourself, "Did I increase the size of my intake valves or are they stock?". Engine design engineers design todays cars perfectly for MPG. Just the right amount of air, fuel, and exhaust for best volumetric efficiency. Manufacturers will argue against K&N cause of 3rd party reasons.
This is wrong. That has absolutely nothing to do with the intake being restrictive. You have to think, your air is restriced by the smallest pipe you have in your intake system. If your intake can only take in so much air, not any more, then the valves can only flow that much air. Valves in modern engines are actually designed big from the factory for a reason of knowing people will probably be doing things to their cars to make them less restrictive and run more efficiently. In my Evo, it is actually useless to get 5mm oversize valves, even if done right, because even after being fully built, it will only net me about 3hp. So valves don't have anything to do really in restrictiveness as they are designed to flow more than the actual head will allow anyways.

Another way you could look at this is just like a turbo. (Most people say you can't compare a NA car to a FI car but just hear me out). If a turbo'd car wants more power what do they do? They do 2 things, 1) raise the boost level, or 2) go bigger weather the whole turbo is changed for something bigger, or they start porting housings and getting bigger wheels. Bigger turbos will ALWAYS have a bigger inducer for the intake. The turbo housing output is generally the same size, but think of it like this. With a 2in opening, it can only flow x amount of air, and that air is put into a 2" pipe that goes to the turbo. Now a bigger turbo has a 4in inducer, so it is drawing x*2 (as it is double the size (yes i know there is more to this but I'm not going to deep into details) and cramming double the air into the same 2" pipe. Now when that happens, this is why guys with big turbos can achieve the same power with less boost, is because they are flowing a lot more air. Same goes with a NA car. Once you have everything flowing the same (intake, engine and exhaust), then you will be at maximum efficiency. That there will allow the best amount of power and the best MPG as there is nothing restricting the engine, so it runs much smoother with less feed back and doesn't have to work as hard to achieve what it's trying to do. Does that make sense?:amuse:
 

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Look at my little diagram and this should explain it much better of what I am referring to.

and your SRI setup, you can clearly see where its lacking.

In order for the intake to actually do what is designed for, you will need a larger intake runner, plenum, intake valve, exhaust valve, exhaust header, camshaft, and a re-tune in order to achieve maximum 0% STFT/0% LTFT volumetric efficiency.

This may be a bit more advance to some, my apologies, but Leevi will understand what I am talking about.
 

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Levee
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Look at my little diagram and this should explain it much better of what I am referring to.

and your SRI setup, you can clearly see where its lacking.
oh I understood what you were saying:amuse:. I'm saying, look at the size of the "snorkel" for the stock air box. It's maybe 1 inch in diameter that brings in outside engine compartment air. that's VERY small. Another thing to think of is that there is 2 valves per cylinder (each valve is 1.38 inches in diameter so basically it flows 2.76in air per time the valves open) which is bigger than the snorkel, so it flows better for sure. You'd be suprised at how much those small valves will flow tho.

I'm not saying by any means that you're wrong, please don't mis read that. I'm saying tho, that the biggest restriction is at the very front of the air system which isn't good. Opening that up will help the cylinders breathe better. Think of trying to vacuum a golf ball through a garden hose. The ball is the air trying to get through that small opening, and the engine is straining to pull that thru, by opening that up is less strain on the engine.
 

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Airbox mod with a K&N drop in. Done

---------- Post added at 06:23 PM ---------- Previous post was at 06:21 PM ----------

Look at my little diagram and this should explain it much better of what I am referring to.

and your SRI setup, you can clearly see where its lacking.

In order for the intake to actually do what is designed for, you will need a larger intake runner, plenum, intake valve, exhaust valve, exhaust header, camshaft, and a re-tune in order to achieve maximum 0% STFT/0% LTFT volumetric efficiency.

This may be a bit more advance to some, my apologies, but Leevi will understand what I am talking about.
Diagram reminds me of the old looney tunes. Wiley coyote with acme blueprints, lol
 

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Discussion Starter #12
Sooooooo what I'm getting from this is that an intake will only do what it's suppose to I you upgrade the other parts? ( intake valve, exhaust valve, etc) or an Aftermarket intake lets the engine breath better due to more available airflow?
 

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Sooooooo what I'm getting from this is that an intake will only do what it's suppose to I you upgrade the other parts? ( intake valve, exhaust valve, etc) or an Aftermarket intake lets the engine breath better due to more available airflow?

Yes you would need to, IF you are looking at the "most" performance from that intake. You would actually run longer intake runners and try to increase the size of the intake plenum (plenum stores the air before it runs through the runners and into the intake valve openings), but we're looking at just street performance. Your K&N or whomever makes your intake kit will allow the engine to breathe a bit better and more of a mass air (weight calculation) can be vacuum'd into the combustion chamber for efficiency. You will also notice a small bit of throttle response since the air is traveling at a performance minded flow.

Now upgrading the other parts of the valvetrain will enhance the more flow once your volumetric efficiency table in your PCM has been calibrated correctly. You have to remember, today's street driven cars are programmed for stoicheometric a/f ratio roughly 14.7:1, 14.7 lbs of air (mass) to 1 lb of fuel. This is more achieved during cruise than WOT. Im not trying to teach a lesson on how to trick today's cars, but its not all that hard science, lol.

Leeveecius, I didnt think anything bad, but that was how my understanding of fuel injected intake systems work and probably outdated by a decade now lol. What I mean to everyone by is on intakes, is if your going to just slap an intake and expect out of this world results in power, it takes a lot more understanding on how the engine works down to the flamefront. :)

If your looking at more MPG, you would think more of unrestricting the engine flow (ability to breathe) and reach that 14.7:1 for max MPG.
 

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lol.

It's all in the right foot.

You guys overcomplicate things that make marginal differences and change via climate and condition of the car as well.

Too many factors.

Hotter air = better MPG's. Done and done.
 

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lol.

It's all in the right foot.

You guys overcomplicate things that make marginal differences and change via climate and condition of the car as well.

Too many factors.

Hotter air = better MPG's. Done and done.
Exactly, I did overdue it a bit. Yes, some marginal, but it depends on what you have for climate, barometric pressure, and what performance parts you have.

Colder air=better combustion, done :bigsmile:
 

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Levee
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Yes you would need to, IF you are looking at the "most" performance from that intake. You would actually run longer intake runners and try to increase the size of the intake plenum (plenum stores the air before it runs through the runners and into the intake valve openings), but we're looking at just street performance. Your K&N or whomever makes your intake kit will allow the engine to breathe a bit better and more of a mass air (weight calculation) can be vacuum'd into the combustion chamber for efficiency. You will also notice a small bit of throttle response since the air is traveling at a performance minded flow.

Now upgrading the other parts of the valvetrain will enhance the more flow once your volumetric efficiency table in your PCM has been calibrated correctly. You have to remember, today's street driven cars are programmed for stoicheometric a/f ratio roughly 14.7:1, 14.7 lbs of air (mass) to 1 lb of fuel. This is more achieved during cruise than WOT. Im not trying to teach a lesson on how to trick today's cars, but its not all that hard science, lol.

Leeveecius, I didnt think anything bad, but that was how my understanding of fuel injected intake systems work and probably outdated by a decade now lol. What I mean to everyone by is on intakes, is if your going to just slap an intake and expect out of this world results in power, it takes a lot more understanding on how the engine works down to the flamefront. :)

If your looking at more MPG, you would think more of unrestricting the engine flow (ability to breathe) and reach that 14.7:1 for max MPG.
This is true.. I won't argue this lol. Unrestricting the flow to, through, and out of the engine is how to achieve the best MPG's as well as better overall power, so to speak. (yes there are more variables to take into consideration, but the general rule of thumb is this)

lol.

It's all in the right foot.

You guys overcomplicate things that make marginal differences and change via climate and condition of the car as well.

Too many factors.

Hotter air = better MPG's. Done and done.
Yes too many factors, but there are a lot of different factors to take into consideration when talking about MPG's. Tune, right foot, and air flow are the 3 biggest ones.

Exactly, I did overdue it a bit. Yes, some marginal, but it depends on what you have for climate, barometric pressure, and what performance parts you have.

Colder air=better combustion, done :bigsmile:
I'll just leave it with that lol. Don't forget, colder air=more fuel/denser air= more power. :)
 

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Discussion Starter #17
As stated above, someone said something about an "airbox mod" with a kn drop in filter. What I an airbox mod? Also, is the stock airbox more of a CAI or Sri
 

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As stated above, someone said something about an "airbox mod" with a kn drop in filter. What I an airbox mod? Also, is the stock airbox more of a CAI or Sri
airbox mod is running the SRI piping, removing the tubing from the bottom of the box, and a K&N drop in filter.
 

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Discussion Starter #19
Hmm what are the advantages of doing that instead of just leaving a stock intake on there and dropping on a kn drop on?

---------- Post added at 12:52 AM ---------- Previous post was at 12:51 AM ----------

Dropping in* lol
 

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Hmm what are the advantages of doing that instead of just leaving a stock intake on there and dropping on a kn drop on?

---------- Post added at 12:52 AM ---------- Previous post was at 12:51 AM ----------

Dropping in* lol
with the piping added, you don't really gain much, looks cooler under your hood, a little quicker throttle response on the tps/app sensor. You can hear a bit of ''growl'' when accelerating. The drop in alone will give it the same quietness, but will increase a few mpgs.
 
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