Anyone driven Honda SIR with cone filters???

[Ghostrider]

Refer to my posting on Auto Dynamac. They can customise a hetshield for you.

 

Mugen box if you want to see go to Waterloo Centre. Ground floor there is one selling Remus exhaust...they used to carry the Mugen Box. But its not cheap hor....JB got cheong ones.

[Ghostrider]

Ditch the resonator box cos it blocks the smooth passage of air flow.

 

What it does is that air will go thru bends in the resonator box to lower the induction noise. It does no other function.

 

I ditch it and in its place I used a flexi hose to direct air into the airbox. Flexi hose extends to the wheel arch area to draw in cool air.

[Cardinal]

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Ask yourself this question :

 

By varying the lenght of the pipe to the airfilter you can tune between improvement in torque or power ?

 

You gotta be kidding me.

 

Both work the same principle. Allow more air flow hence better combustion. CAI is good for more power as it draws cool air only. But not very practical for daily use as filter gets dirty very easily and not friendly to floods.

 

SRI stays within your engine bay...problem when people do not have a heat shield for this as the filter ends up sucking hot air instead of cold air losing power in the process.

 

There is some truth to the statement that a different length intake affects HP and torque. Basically, intake diameter and length (and curve) affects velocity of airflow into combustion chamber, just like exhaust diameter and shape (mandrel etc) affects velocity of airflow out of the combustion chamber.

 

For any setting of intake and exhaust valve timings, overlap, and even ignition timing, there is an optimum airflow velocity to generate the most power. That's why there is peak torque and HP at a certain RPM for any engine. That's also why a certain intake length, or exhaust diameter, affects the power and torque.

 

I'm just saying that intake length and diameter does affect power delivery. As to how, specifically an SRI vs CAI affects the power band, it's beyond me you have to ask the experts on this. But so far, I've yet to come across a consistent enough explanation that I find easy enough to understand.

[Yttrium]

From what I know, intake manifold length/diameter does have a profound effect on power/torque. Certain Honda (and I'm sure other makers too) engines used a two-path intake manifold, a longer one for improved torque in the low to mid rpm range and a shorter one for improved top-end power. BMW takes it a step further with a fully variable length system that maximises efficiency at all engine speeds. All these make use of the timing of the incoming pressure waves with the engine speed, the pressure waves in effect giving a "turbocharging" effect.

 

However, when it comes to the intake pipe upstream of the filter I doubt there is such a big or any effect from tuning the length since the pressure waves would be broken up by the filter element? Same thing for the Twister ducted cone filter I'm using, I seriously doubt the swirl effect induced can be maintained after the airflow passes through the cone filter. What do you think?

[Ghostrider]

On the intake...I doubt there is any difference as your throttle body will moderate/limit the airflow into the combustion chamber. On the exhaust side, I agree that piping size, the bends wil have a effect on the power. This is becasue there is no restriction...which is why in the first place why people mod their stock exhaust system to remove restrictions.

 

But too free flowing is bad too as there is no back pressure and car will feel slugish. If one do not mind to rev their engine to get to the powerband, then its still acceptable for them...but for those who do not exceed 4000rpm...they will pull their hair out.

 

One thing to note about the route of the air...the more bend there is...the lesser velocity of the charge. EG. those who install aircon...they will seek the shortest most direct route to send the cold air from compressor to fan coil as the more bend there is...the less powerful the unit becomes. I cannot remember how to calculate liao...but for every bend...the compressor loses a couple of BTU. [reply]

 

[Yansen]

oic. hehe thought u wanted to increase the noise only. hmm btw now i'm using stock airbox with k&n drop in filter. maybe can follow ur method. u said 'Flexi hose extends to the wheel arch area to draw in cool air. ' so is this considered a form of CAI also?

[Ghostrider]

Using your stock box will min the induction noise. You can use the method that I mentioned. Just go to your mech and ask them to remove the resonator box and in its place just do a piping to direct cold air into the airbox.

 

Do not pipe it all the way down as when there is flood, the water will be sucked up to the engine...don't underestimate the power of induction.

 

It is a form of cold air intake.

 

Advantage is that...

 

1) Lesser induction noise

2) Stock airbox act like a heat shield

[Cardinal]

I thot the purpose of intake mod is to have that induction noise which sounds good when you rev?

[Cardinal]

Well, like Yttrium said, there is variable length intake manifold, which changes the power of the engine at different RPMs. So similarly, a different length will have some effect.

 

But I think I know where you are coming from: you don't normally tune an engine's HP by varying the intake, cos the intake has a very limited influence. I'd agree with you. Usually, you just go for the least restictive intake that is able to take in the coolest air temperature, and then concentrate on modding other parts of the engine.

[Cardinal]

  Quote

However, when it comes to the intake pipe upstream of the filter I doubt there is such a big or any effect from tuning the length since the pressure waves would be broken up by the filter element? Same thing for the Twister ducted cone filter I'm using, I seriously doubt the swirl effect induced can be maintained after the airflow passes through the cone filter. What do you think?

 

yeah, agree with you that intake length upstream of the filter prob doesn't affect much except restrict the airflow. But if the air taken in is much cooler, then it's a pretty good tradeoff.

 

the other thing to think about it: it's so easy to implement a twister system to have a swirl effect going into the engine bay, so why do car manufacturers not incorporate it in the first place? It doesn't increase noise or have other negative effects, and it's cheap to manufacture (they prob have more then enough technology to be able to design fan blades).

[Yttrium]

Coz it doesn't work?

That swirly thingy is probably a marketing gimmick lah... or else they cant' give it a fancy name like "Twister" mah

[Ghostrider]

Ya rite...then some system should be term as all sound no go liao lor....ha ha ha ha ha....

[Ghostrider]

Actually they have. The Mitsubishi Toppy Town Bee (sub 1L car) has the tumbling effect thingy...dunno what is it called liao but it was said to be the start of the GDI techology.

 

The bugger works...cos the TownBee was able to hit 22km/L comsumation !! On the road, many reported around 19km/L which is a remarkable fig.

[Yttrium]

This would be somewhere along the intake manifold or inside the cylinder right?

 

Yeah I'm sure they have these technologies to induce swirl to get a more complete combustion process. But anything that claims to be able to attain any beneficial effects by inducing swirl upstream of the throttle body is doubtful.

[Yansen]

hmm ic thanks. for the piping do i have to use the flexi pipe?

 

btw abt the advantages u mentioned, y is it that without the resonator, the induction noise will be reduced? i thought the resonator is to reduce the induction noise?

[Ghostrider]

Just before the throttle body.

 

Actually if some sort of device like the electric aircharger who pushes air after the filter is workable. My friend who used it before said it was effective.

[Ghostrider]

Use flexi pipe is better. Easier to route the pipe around. You can find these pipes of various sizes at Lavender Street.

 

I mean the induction noise is reduce because you kept the orginial air filter box intact. hence it helps mask the induction noise. If you are using those open pod filter, the induction noise can be quite loud to some people. You need to remove the resonator box so that you can route the pipe in its place.

[Rustycar]

  Quote

Coz it doesn't work?

That swirly thingy is probably a marketing gimmick lah... or else they cant' give it a fancy name like "Twister" mah .....

 

... Yeah I'm sure they have these technologies to induce swirl to get a more complete combustion process. But anything that claims to be able to attain any beneficial effects by inducing swirl upstream of the throttle body is doubtful.

 

You mean your Twister doesn't give u better performance? I felt a mark difference for mine. Overall throttle response and mid-high range very different from stock.