The Reason Why Cars Uses an Air Box

[Satria_neo]

It took me a long time but I finally find out why.

 

Its due to Helmholtz resonance.

 

http://en.wikipedia.org/wiki/Helmholtz_resonance

 

This is brings me to think about the Ninja Air Intake. the cylinder after the filter looks like a large cavity. Then the tube (assuming it has a valve/actuator) connects to the engine valve cover (I guess to increase the pressure inside the cylinder).

 

Hmm.... if its really true, then Ninja air intake does work on principle of Helmholtz resonance. Maybe can DIY something to test.

[Good-Carbuyer]

It took me a long time but I finally find out why.

 

Its due to Helmholtz resonance.

 

http://en.wikipedia.org/wiki/Helmholtz_resonance

 

This is brings me to think about the Ninja Air Intake. the cylinder after the filter looks like a large cavity. Then the tube (assuming it has a valve/actuator) connects to the engine valve cover (I guess to increase the pressure inside the cylinder).

 

Hmm.... if its really true, then Ninja air intake does work on principle of Helmholtz resonance. Maybe can DIY something to test.

Installed parallel air filter to Fiat Uno and got about 10% better FC. Engine slightly noiser, acceleration may be a little better, but I was more concerned with the FC improvement. Installed cold air intake for Hyundai Accent and got better acceleration. Noise and FC remain about the same. Hope these of some use for your DIY. Current Myvi seems congested for any such DIY tinkling, only inflate tire a little more.

[SimonTan]

I think it works more on the exhaust pipe scavenging of hot air.

The intake should matter less, as long as the air box is big enough to accommodate the air filter. Me think the air filter is limiting the designer to reduce the intake air box to a much smaller package.

 

[Badder]

Installed parallel air filter to Fiat Uno and got about 10% better FC.

 

SNIP

 

 

Installed cold air intake for Hyundai Accent and got better acceleration.

 

 

no you didnt

 

[Bighappyjer]

no you didnt

 

I agree. Butt feel perhaps

[Daniellah]

I have a Ninja V2 for sale. Didn't like the noise after installing. Letting go at $80. Contact me at 98802831

 

[Zuoom]

as in stock cars?

 

mostly for noise.

[Watwheels]

It's just a muffler at the air intake end for sound reduction, very much like the one at the exhaust. Ppl are kidding themselves with the "cold air intake" just becos it's noisy, it improves nothing. The significant move is modifying the size of air intake manifold which LTA does not allow. Those ninja butt crap are just snake oil.

[Good-Carbuyer]

no you didnt

[Satria_neo]

It's just a muffler at the air intake end for sound reduction, very much like the one at the exhaust. Ppl are kidding themselves with the "cold air intake" just becos it's noisy, it improves nothing. The significant move is modifying the size of air intake manifold which LTA does not allow. Those ninja butt crap are just snake oil.

 

I don't know much about the ninja thing but it does seems to use this effect. I could be wrong, just a guess.

 

As for CAI. Actually it does help if its properly made. I have completed my DIY air intake and it beats the stock intake flat out!

 

Actually stock intake is rarely the best. ITs made that way because bo pian. Optimum intake is actually a long straight pipe of a certain diameter and length. It will give the fastest air flow into the engine. But it cannot be done due to space constrain (imagine a pipe sticking out of the side of your car). Hence engineers have to bend the pipes around and all these bend only slow down the air velocity and reduce performance esp. at low RPM.

 

If you can eliminate or reduce as much of these bends as possible, you will be able to improve air velocity. Then experiment around to find out optimum length for the intake.

[Watwheels]

I don't know much about the ninja thing but it does seems to use this effect. I could be wrong, just a guess.

 

As for CAI. Actually it does help if its properly made. I have completed my DIY air intake and it beats the stock intake flat out!

 

Actually stock intake is rarely the best. ITs made that way because bo pian. Optimum intake is actually a long straight pipe of a certain diameter and length. It will give the fastest air flow into the engine. But it cannot be done due to space constrain (imagine a pipe sticking out of the side of your car). Hence engineers have to bend the pipes around and all these bend only slow down the air velocity and reduce performance esp. at low RPM.

 

If you can eliminate or reduce as much of these bends as possible, you will be able to improve air velocity. Then experiment around to find out optimum length for the intake.

This is exactly the misconception that most ppl have. Yes, a straight pipe does have a more direct air flow but the air stops at the resonance box or air box which acts like a reservoir to store air before entering the air intake manifold. A lot of ppl do not know this but the volume of the air box has the same volume of your air intake manifold. Whatever the air needed to enter the manifold is "stored" at the air box hence before the air box the pipping layout is straight or not have no effect except the noise it creates.

 

Unless you dyno the before & after on the modification on your air intake and have yield significant results, otherwise to me it's just sound effects.

 

I have observe cars which have a straight pipping leading to the air box vs cars which have a series of bends before the air box the difference is in the sound when the car accelerates hard. Straight pipping layout gives a loud chainsaw like coarse sounding effect while the series of bends gives a subtle smoother sound during hard acceleration. If you read car reviews which the car reviewer mentions about the coarse sounding effect during hard acceleration you can more or less guess the pipping layout the car is using.

 

A good example is the sewage pipping layout that you see in your toilet. They can make the pipping straight from the top floor all the way to the ground floor what, why they make so many complicated bends that can sometimes choke the pipes? The reason is to minimize the noise it creates when sh*t, urine & water pass thru the pipping. So that you dun get wake up in the middle of the night everytime your neighbour visits the toilet.

Edited October 17, 2011 by Watwheels

[Satria_neo]

This is exactly the misconception that most ppl have. Yes, a straight pipe does have a more direct air flow but the air stops at the resonance box or air box which acts like a reservoir to store air before entering the air intake manifold. A lot of ppl do not know this but the volume of the air box has the same volume of your air intake manifold. Whatever the air needed to enter the manifold is "stored" at the air box hence before the air box the pipping layout is straight or not have no effect except the noise it creates.

 

Unless you dyno the before & after on the modification on your air intake and have yield significant results, otherwise to me it's just sound effects.

 

I have observe cars which have a straight pipping leading to the air box vs cars which have a series of bends before the air box the difference is in the sound when the car accelerates hard. Straight pipping layout gives a loud chainsaw like coarse sounding effect while the series of bends gives a subtle smoother sound during hard acceleration. If you read car reviews which the car reviewer mentions about the coarse sounding effect during hard acceleration you can more or less guess the pipping layout the car is using.

 

A good example is the sewage pipping layout that you see in your toilet. They can make the pipping straight from the top floor all the way to the ground floor what, why they make so many complicated bends that can sometimes choke the pipes? The reason is to minimize the noise it creates when sh*t, urine & water pass thru the pipping. So that you dun get waked up in the middle of the night everytime your neighbour visits the toilet.

 

No you are wrong. The bends in the pipes is not for noise purpose. Its meant for smell.

 

W/o those bends, your whole house will smell like sewage. The bend traps water. This water acts as a barrier so the air inside the sewage pipe will not escape into your toilet.

[Yc86]

It took me a long time but I finally find out why.

 

Its due to Helmholtz resonance.

 

http://en.wikipedia.org/wiki/Helmholtz_resonance

 

This is brings me to think about the Ninja Air Intake. the cylinder after the filter looks like a large cavity. Then the tube (assuming it has a valve/actuator) connects to the engine valve cover (I guess to increase the pressure inside the cylinder).

 

Hmm.... if its really true, then Ninja air intake does work on principle of Helmholtz resonance. Maybe can DIY something to test.

 

The ninja air_intake is not a helmoltz resonance device because it is not an airbox. it doesn't not 'store' any air because its inlet and outlet diameters are pretty much the same, and it has a very low volume.

 

To have a helmholtz resonance effect, you need a 'stored' volume of air. The stock airbox has an inlet, which is smaller than its outlet. This creates a pressure difference between the inside of the box and atmosphere, and a difference between inside the box and intake manifold.

 

To put it into perspective, the older 3L v10 F1 cars had an airbox volume of approx 50 litres.

 

From the pics at the ninja site, it looks like the volume inside is about 1-2 litres.

 

The site isn't very impressive also btw.

[Expertz]

No you are wrong. The bends in the pipes is not for noise purpose. Its meant for smell.

 

W/o those bends, your whole house will smell like sewage. The bend traps water. This water acts as a barrier so the air inside the sewage pipe will not escape into your toilet.

 

 

mister, go and try standing behind your car's exhaust, do you feel like as if there is a huge turbine blowing out of your exhaust? or do you find that the amount of exhaust gas produced increased after changing your air intake?

if no then i can assure you that your huge straight pipe air intake doesn't increase the amount of air going into your engine

 

there is a reason why car manufacturers tend to buy engines from other manufacturers and tweak it rather than to design a complete new engine. a new engine costs hundreds of thousands of dollars despite the blueprint being the same

the hundreds of thousands of dollars goes into testing the engine for emissions, torque, power and fuel economy

if a simple $100 changing of the airbox will increase fuel economy or torque and power, then its thousands of dollars wasted by the manufacturer

same reason why petrol doesn't come with aftermarket addictives, if those stuff work, the big oil companies would have added those into their petrol from the onset

[Satria_neo]

mister, go and try standing behind your car's exhaust, do you feel like as if there is a huge turbine blowing out of your exhaust? or do you find that the amount of exhaust gas produced increased after changing your air intake?

if no then i can assure you that your huge straight pipe air intake doesn't increase the amount of air going into your engine

 

there is a reason why car manufacturers tend to buy engines from other manufacturers and tweak it rather than to design a complete new engine. a new engine costs hundreds of thousands of dollars despite the blueprint being the same

the hundreds of thousands of dollars goes into testing the engine for emissions, torque, power and fuel economy

if a simple $100 changing of the airbox will increase fuel economy or torque and power, then its thousands of dollars wasted by the manufacturer

same reason why petrol doesn't come with aftermarket addictives, if those stuff work, the big oil companies would have added those into their petrol from the onset

 

Yes, the amount of exhaust gas produced did increased by around 5%.

 

[Satria_neo]

mister, go and try standing behind your car's exhaust, do you feel like as if there is a huge turbine blowing out of your exhaust? or do you find that the amount of exhaust gas produced increased after changing your air intake?

if no then i can assure you that your huge straight pipe air intake doesn't increase the amount of air going into your engine

 

there is a reason why car manufacturers tend to buy engines from other manufacturers and tweak it rather than to design a complete new engine. a new engine costs hundreds of thousands of dollars despite the blueprint being the same

the hundreds of thousands of dollars goes into testing the engine for emissions, torque, power and fuel economy

if a simple $100 changing of the airbox will increase fuel economy or torque and power, then its thousands of dollars wasted by the manufacturer

same reason why petrol doesn't come with aftermarket addictives, if those stuff work, the big oil companies would have added those into their petrol from the onset

 

Anyway, no point discussing or rather arguing cause I am just wasting my time if I were to try to explain to you. So lets just forget it.

 

You enjoy your ride, I enjoy mine. Thats all it matters.

[Mecontle]

No you are wrong. The bends in the pipes is not for noise purpose. Its meant for smell.

 

W/o those bends, your whole house will smell like sewage. The bend traps water. This water acts as a barrier so the air inside the sewage pipe will not escape into your toilet.

 

g damn even toilet studies need so much careful design

[Mecontle]

mister, go and try standing behind your car's exhaust, do you feel like as if there is a huge turbine blowing out of your exhaust? or do you find that the amount of exhaust gas produced increased after changing your air intake?

if no then i can assure you that your huge straight pipe air intake doesn't increase the amount of air going into your engine

 

there is a reason why car manufacturers tend to buy engines from other manufacturers and tweak it rather than to design a complete new engine. a new engine costs hundreds of thousands of dollars despite the blueprint being the same

the hundreds of thousands of dollars goes into testing the engine for emissions, torque, power and fuel economy

if a simple $100 changing of the airbox will increase fuel economy or torque and power, then its thousands of dollars wasted by the manufacturer

same reason why petrol doesn't come with aftermarket addictives, if those stuff work, the big oil companies would have added those into their petrol from the onset

 

depends on car type, eco car like vios r factory r tuned for mpg but some makeover can make some diff