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Old 17th December 2010, 15:22   #46
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Default Re: Aspects of designing an Air Intake Revision

In the case of Esteem MPFi's setup, I could not see any twist and turns in the plumbing and it looks like a fair and straight forward setup compared to other cars.
Is it such short pipe the reason why esteem suffers from severe low initial torque??
Could a lesser diameter pipe would increase the initial torque and how much could that affect the top-end power?

sarmarishi i hope you wont mind using your picture here
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Old 17th December 2010, 16:08   #47
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Default Re: Aspects of designing an Air Intake Revision

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Originally Posted by CPH View Post
This is not the worst solution one could think of as space is abit of a problem. However there is room for improvement, which I wll look into when I am over in Mumbai (I am leaving for Mumbai in less than 1 hour).
Great will wait to hear from you on that then.

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Originally Posted by aa_asif View Post
In the case of Esteem MPFi's setup, I could not see any twist and turns in the plumbing and it looks like a fair and straight forward setup compared to other cars.
Is it such short pipe the reason why esteem suffers from severe low initial torque??
Could a lesser diameter pipe would increase the initial torque and how much could that affect the top-end power?

sarmarishi i hope you wont mind using your picture here
Not at all. Maybe it is the length and the rather straighter setup of the intake because of which the Esteem has a rather sad low end torque and may be it is because of the same reason that you can red-line the machine in 1st, 2nd and 3rd gears and it propels like a rocket! I just love the amount of stretching that one can do through the gears in the Esteem esp the 2nd and 3rd!
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Old 17th December 2010, 21:37   #48
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Default Re: Aspects of designing an Air Intake Revision

@DNS

Judging from your pictures i don't think there's space enough for an alternate routing of the intake if you insist on using the current conical filter.

A Hoodscoop might be an extreme option.

Is it possible to use the existing stock entry duct along with a hood scoop filter element? Going by your pics it does look similar from my perspective.

Last edited by di1in : 17th December 2010 at 21:38.
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Old 18th December 2010, 02:02   #49
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Default Re: Aspects of designing an Air Intake Revision

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Originally Posted by DNS View Post
Hi CPH,

This discussion has brought up a few doubts about the installations on my car. Also, i have very little knowledge about Air intakes.
I have fitted a Green Cotton - Wind CAI.

1. The green circle indicates the Stock position/duct of the intake. It seems to be in a good position, at the boundary of the engine bay (low heat) & taking in air from the front grill and space between the bonnet and grill.

2. The white circle indicates the (much disliked here) flexible pipe from the filter to the stock entry duct. To begin with, what is the solution to the flexible pipe itself. Second, the flexi pipe is taking a full 180* turn, going further down into the (hot) engine bay, to then connect to the duct. I have stared at the engine bay for a while now and: -
a) Due to the fitting of the filter, there is no path to the current entry duct besides the way it is now.
b) In the case that the entry duct should be moved, i ask where to? I don't understand flow dynamics.

3. The red circle indicated the plastic stock piping after the filter. This has a significant bend, and is also very close to the exposed mid-section of the engine (heat soak). I think its safe to assume there is very little i can do there.

Request your professional help/suggestions.

Thanks CPH
You are better off without the convulated hose before the filter element. I will look deeper into the engine, but need to see it in the flesh.

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@DNS

Judging from your pictures i don't think there's space enough for an alternate routing of the intake if you insist on using the current conical filter.

A Hoodscoop might be an extreme option.

Is it possible to use the existing stock entry duct along with a hood scoop filter element? Going by your pics it does look similar from my perspective.
I am sure we find some space.

Stock entry duct with hood scoop can be tricky depending on weather.
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Old 18th December 2010, 09:56   #50
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Default Re: Aspects of designing an Air Intake Revision

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Originally Posted by CPH View Post
You are better off without the convulated hose before the filter element. I will look deeper into the engine, but need to see it in the flesh.



I am sure we find some space.

Stock entry duct with hood scoop can be tricky depending on weather.
This is the usual set-up for Pete's Swifts. If you want to install the box, the engine needs to breath better, hence the recommended (by pete's) Green Cotton - Wind. If you can find a peted swift while you are down in Mumbai, which shouldn't be that hard, you can have a look and let us victims know. With regards to the space under the hood, it is very very tight. Like you said, a scoop entry duct can be very tricky with weather, and also would suck in more dust and pollution. If I were to go for this set-up, would I have to change the Green Cotton - Wind filter. Thanks, DNS
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Old 23rd December 2010, 10:16   #51
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Default Re: Aspects of designing an Air Intake Revision

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What is the function of this breather valve?

And why do most people lose power on low rpms with a CAI?
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Old 23rd December 2010, 10:30   #52
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Default Re: Aspects of designing an Air Intake Revision

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What is the function of this breather valve?
That's the crank case breather, it allows the crankcase to breathe and the fumes coming out of it are diverted back into the engine to burn in the chamber. Now it just vents off into the atmosphere.

Quote:
And why do most people lose power on low rpms with a CAI?
Intake velocity. With most aftermarket bolt on CAI installations the intake velocity drops, and that is bad for low RPM torque.
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Old 23rd December 2010, 15:07   #53
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Default Re: Aspects of designing an Air Intake Revision

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Originally Posted by Sankar View Post
That's the crank case breather, it allows the crankcase to breathe and the fumes coming out of it are diverted back into the engine to burn in the chamber. Now it just vents off into the atmosphere.
So what is the advantage of this external crankcase breather. It's just a pipe coming out the crankcase right. Or is there more to it?

Quote:
Originally Posted by Sankar View Post
Intake velocity. With most aftermarket bolt on CAI installations the intake velocity drops, and that is bad for low RPM torque.
Most? So is it possible to increase intake velocity without decreasing the silicon tube dia? Is that why some people use a longer straight tube leading to the intake manifold?

Thanks for answering my Qs!
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Old 23rd December 2010, 16:00   #54
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Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by Sankar View Post
Intake velocity. With most aftermarket bolt on CAI installations the intake velocity drops, and that is bad for low RPM torque.
@Sankar, I thought a better filter will help increase the air flow & In-take velocity into the engine (after the filter) - irrespective of the CAI. Why do you say that the in-take velocity drops ?
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Old 23rd December 2010, 17:12   #55
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Default Re: Aspects of designing an Air Intake Revision

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Originally Posted by di1in View Post
So what is the advantage of this external crankcase breather. It's just a pipe coming out the crankcase right. Or is there more to it?
Crankcase has to be depressurised and the vent does the job, with the gases being routed back into the manifold is good for environment as the fumes gets burned. If its a PCV system it should be connected to the intake manifold to work well. Else vent to the air.

Quote:
Most? So is it possible to increase intake velocity without decreasing the silicon tube dia? Is that why some people use a longer straight tube leading to the intake manifold?

Thanks for answering my Qs!
Quote:
Originally Posted by condor View Post
@Sankar, I thought a better filter will help increase the air flow & In-take velocity into the engine (after the filter) - irrespective of the CAI. Why do you say that the in-take velocity drops ?
CPH had explained this before in this thread, most aftermarket systems use the incorrect intake piping diameter and length. The filter may flow well, but the pipe will not do its job of maintaining gas velocity.

The tube diameter has to be matched to the engine characteristics and the target RPM, this involves a bit of calculation which i have not attempted. And i don't think there is an easy way to obtain the correct intake velocity to work efficiently at all RPM ranges without doing some math!
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Old 23rd December 2010, 17:15   #56
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Default Re: Aspects of designing an Air Intake Revision

diameter of the filter / pipe - does it have a role to play with the amount of air sucked in at a particular RPM? i think velocity of air we can suck in using two straws (with different diameter) is different.

Please correct me if i am wrong.

EDIT: Thanks Sankar.

Last edited by planet_rocker : 23rd December 2010 at 17:16.
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Old 23rd December 2010, 17:48   #57
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Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by Sankar View Post
Crankcase has to be depressurised and the vent does the job, with the gases being routed back into the manifold is good for environment as the fumes gets burned. If its a PCV system it should be connected to the intake manifold to work well. Else vent to the air.
Yeah, but what is the benefit of venting to the air? The fumes from the crankshaft were assumed to be below 2% in one of the articles i'd read. Since they have unburnt fuel in them as well - is it really bad?
Quote:
Originally Posted by Sankar View Post
The tube diameter has to be matched to the engine characteristics and the target RPM, this involves a bit of calculation which i have not attempted. And i don't think there is an easy way to obtain the correct intake velocity to work efficiently at all RPM ranges without doing some math!
Flexible hoses: turbulence
Metal Pipe: heat soak
Wide plumbing: lower gas velocity
But doesn't that mean that most of the k&nd cars running about are more like conned cars!?

OT: Does a similar gas velocity priciple apply on exhausts?
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Old 23rd December 2010, 18:18   #58
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Default Re: Aspects of designing an Air Intake Revision

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Originally Posted by di1in View Post
Yeah, but what is the benefit of venting to the air? The fumes from the crankshaft were assumed to be below 2% in one of the articles i'd read. Since they have unburnt fuel in them as well - is it really bad?
Benefits can be had if an oil catch can is put between the intake and the crank vent, the can will catch oil mist and will not let that go into the intake, which helps in keeping the TB clean, air fuel charge clean. If venting into the atmosphere directly same benefits can be had but at the expense of polluting.

Yes it does its bit in polluting. If everyone start doing this it'll be bad.

Quote:
OT: Does a similar gas velocity priciple apply on exhausts?
Yes it does.

Last edited by Sankar : 23rd December 2010 at 18:28.
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Old 23rd December 2010, 18:39   #59
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Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by di1in View Post
Yeah, but what is the benefit of venting to the air? The fumes from the crankshaft were assumed to be below 2% in one of the articles i'd read. Since they have unburnt fuel in them as well - is it really bad?


Flexible hoses: turbulence
Metal Pipe: heat soak
Wide plumbing: lower gas velocity
But doesn't that mean that most of the k&nd cars running about are more like conned cars!?

OT: Does a similar gas velocity priciple apply on exhausts?
The reason why the crank case has got to be vented is the pressure build up in the crank case. If not vented it will blow either the front or the rear crank seal and will lead to total oil loss.

Regarding the conned conclusion you are spot on.
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Old 23rd December 2010, 19:41   #60
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Default Re: Aspects of designing an Air Intake Revision

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Originally Posted by Sankar View Post
Does a similar gas velocity priciple apply on exhausts?

Yes it does.
Could you give me some links on where I could read about that please.
Moreover, does this mean the FFE i got just pushed the power band up and made me lose out on lower rpms?? I did feel that initially but I had put the blame on to the upsized wheels&tires.

In a FFE + CAI car where both systems are the poplular ones available easily (conned), will the low rpm drop be greater?

Quote:
Originally Posted by CPH View Post
Regarding the conned conclusion you are spot on.
What do i do if i need a good CAI?
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