Go Back   Team-BHP > Under the Hood > Technical Stuff


Reply
 
Thread Tools Search this Thread
Old 13th December 2010, 20:32   #31
Team-BHP Support
 
Vid6639's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 14,467
Thanked: 19,374 Times
Default Re: Aspects of designing an Air Intake Revision

Anyone heard of ITG air filters. The online reviews sound very promising. Three layer filtration. First a coarse foam layer, then a medium grade foam centre layer and a last fine mesh inner layer. Coupled that with oil.

Looks to be the best filtration and probably better than paper.

CPH, any insights into ITG?
Vid6639 is offline   Reply With Quote
Old 14th December 2010, 00:06   #32
Senior - BHPian
 
khoj's Avatar
 
Join Date: Sep 2008
Location: Dilli
Posts: 2,722
Thanked: 1,253 Times
Default Re: Aspects of designing an Air Intake Revision

Thank you CPH. I appreciate the gesture & the effort.

Quote:
Originally Posted by CPH View Post
I follow khoj's request
I am posting below photographs of a Cosworth CAI installed in my Swift with the 1.3 L petrol engine. The kit is manufactured by Cosworth specifically for the Swift (per Cosworth India) and was installed by Cosworth's own engineer at their India HO in Pune.
Name:  Cosworth CAI.JPG
Views: 3556
Size:  46.0 KB
I have also quoted your first post where the areas of concern wrt to the kit installed in my car have been reproduced in bold. If you could let me have your observations/comments/suggestions on the installed kit wrt to the same and otherwise, it would be of great help.

Name:  CAI Breather Valve.JPG
Views: 2561
Size:  38.7 KB

This kit comes along with a breather valve. Per the Cosworth engineer this is a two way valve and helps maintain a certain volume of air at a certain pressure in the cylinder head by either breathing in or out as the requirement might be. As to the 'certain' values the reply was it is per design and they are specific to the Swift's 1.3 L engine as the kit is designed for the same.

Quote:
Originally Posted by CPH View Post
The objective of the performance oriented designer of an AIR is to get as much air into the engine at any given rpm as well as any given speed. Sounds logical. Sounds simple.

It would be simple if we wouldn't have to deal with the laws of flow dynamics. Flow dynamics is as much a blessing as it is a curse.

To start with we have to look at 2 scenarios, which have distinctive design differences.

1. Normally aspirated AIRs
2. Force induced AIRs
Unless the latter is just another fancy name for Turbo charged, which one is this?

Quote:
Originally Posted by CPH View Post
Next point to figure is where do we have the lowest amount of heat drawn in. Finding such a space is not always difficult. But having fouind that position for the intake we have to deal with more problems. If the car is stationary a smooth intake might work best. this can change dramatically when the car is moving due to turbulences increasing with speed because of the chassis and engine bay design. This can have as much of an input whether the air drawn from in side the engine bay or with a closed system with a snorkel coming in from the front. A CAI in many cases does not work as they are not professionally placed.
Name:  CAI Alternate View.JPG
Views: 2482
Size:  44.4 KB

How is the placement in this case? I did enquire and was advised that there was no heat shield available. I am wondering whether heat rising from the cylinder head can be conducted on to the air intake pipe running over it. Should this be a concern in our local ambient conditions.

Quote:
Originally Posted by CPH View Post
The above mentioned problems we find in normally aspirated AIRs too. The only difference is the design of the pipe before the throttle body. What wee are aiming to get the best results is a combination of gas speed and inertia. The gasspeed is dependent on the rpm.

The higher the gas speed the better it is throughout the rpm range. But physics hits us there. To maintain a certain speed, we need to make the diameters accordingly. If we are goiong to small we have good torque but lose high end. If we go too big we gain peak power but will loose bottom end torque. We can use some tricks to overcome rthis partly, but theses tricks have their limitations too.
Name:  Air Intake.JPG
Views: 2307
Size:  39.3 KB

Two views of the air intake pipe. Though it is not clear but the mouth of pipe is just behind the radiator fan.

Name:  Air Intake Pipe.JPG
Views: 2406
Size:  38.6 KB

The pipe can be elongated further and the bend radius can be increased if need be.

Name:  Pipe diameter.JPG
Views: 2313
Size:  41.4 KB
Is the pipe diameter sufficient. It is about 4" for the initial run of the PVC tube and reduces to around 2.5" after the conical filter, I did not measure just quoting by visual reference.

Quote:
Originally Posted by CPH View Post
Bends should be kept as a minimum and when needed the best results are achieved if the bend is about 10 degrees overbent and then corrected back by the 10 degrees.
Name:  Bend from front.JPG
Views: 2268
Size:  46.4 KB

Is the bend radius sufficient?

Quote:
Originally Posted by CPH View Post
CAIs need a lot of research and engineering to work and can't just be linked to the front at will when advantages are to be expected. The often disturb the rather still air badly when the car is moving, which is bad news.
I can only hope that coming from Cosworth the kit is an outcome of proper research. I was quite hesitant of installing the same but the Cosworth name drew me in.

Overall I have observed some increase in initial response from the engine at low RPMs. The car now pulls cleaner and quicker from standing starts as also roll ons in second gear from crawling speeds at say 1200 ~ 1300 RPM have definitely improved. I cannot comment on improvements in top speeds as on my Bombay Delhi run in this car I restricted the top speed at 110 Kmph. there is no change in the fuel consumption after kit installation it remains steady at 12 Kmpl with 100% air con. On the highway run the mileage was 14 Kmpl after the install, this is the same as my numerous runs on Bom - Pune Xpressway and Nasik / Goa highways prior to the install. Again top speeds were restricted at 110kmph on the Xpressway and 80~90 kmph on the other highways.

A fellow member had put forth an interesting point regarding these CAIs. Per his view the large diameter of the intake pipe would allow more dust etc to be carried into the filter resulting in either these filters becoming choked thereby impeding air intake or in others it would allow fine granules to pass through the filter on account of the increased air flow speed and the high volume being sucked in and thereby damaging the engine. This has kept me from installing a direct bolt on kit made specifically by 'PiperCross' for the Cedia on mine. Let me have your views on the above. BTW the Cosworth filter does not need any oil etc for cleaning. I was advised to take it off maybe once in a couple of years and to blow air in from the opposite end using an ordinary vacuum cleaner running in reverse or even a hair dryer blower without the heat on.

Last edited by khoj : 14th December 2010 at 00:21.
khoj is offline   Reply With Quote
Old 14th December 2010, 00:27   #33
Senior - BHPian
 
pranavt's Avatar
 
Join Date: May 2008
Location: Mumbai
Posts: 1,628
Thanked: 272 Times
Default Re: Aspects of designing an Air Intake Revision

The Cosworth setup is crap because of the stupid blue flexible pipe. That thing will introduce turbulence into the intake charge which is undesirable unless you want to mix fuel with air.

The rest of the theory is mostly irrelevant because something so basic has been overlooked so badly.

Quote:
Originally Posted by Sprucegoose View Post
@pranavt: ahhh.. cool, i know it'll be tough to implement was just considering a hypothetical situation.

Didn't know that F1 engines had them.

I was also thinking about concentric piping for the intake.
A thin one & a co-axially aligned thicker one.
There will be a shutter type valve between the 2 pipes.
The Thin Pipe is always open, but the thicker one opens only after a particular RPM.

again i have no intention of implementing it, was just wondering.

Something similar has already been used on a few Honda motors like the H22, etc

Last edited by pranavt : 14th December 2010 at 00:33.
pranavt is offline   Reply With Quote
Old 14th December 2010, 08:56   #34
BHPian
 
AJITHAAA's Avatar
 
Join Date: Jan 2008
Location: Bangalore
Posts: 110
Thanked: 216 Times
Smile Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by Sankar View Post
CPH, what do you think about this stock AStar air intake? Unlike other modern airboxes this looks simple. But the air intake pipe instead of being simply straight has a series of minor bends in it, that looks purpose fully done. Why so? Do you think a revised intake would be better in this car too?

Attachment 465691
Attachment 465692
Attachment 465693
Check the underside of the hood, the bends might be provided to clear interferences with strengthening panels of the hood. Or this molded hose might be from a different car which is obsolete now and in inventory so the are just using it up. But that should not make any difference to the car performance.
AJITHAAA is offline   Reply With Quote
Old 14th December 2010, 10:39   #35
Distinguished - BHPian
 
Join Date: May 2005
Location: KL
Posts: 4,680
Thanked: 3,507 Times
Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by AJITHAAA View Post
Check the underside of the hood, the bends might be provided to clear interferences with strengthening panels of the hood. Or this molded hose might be from a different car which is obsolete now and in inventory so the are just using it up. But that should not make any difference to the car performance.
The strengthening panels are covered under the black heat/noise shield making the underside of the hood uniform.

This airbox and pipe is not being used by any other car in the Maruti line-up. Apparently the new 1.2liter Swift has a similar airbox with a similarly shaped but longer pipe.

There should be a reason as to why the pipe is made in that fashion, and that is what i want to know, because a straight pipe is much more easier to make and will cost less.
Sankar is offline   Reply With Quote
Old 14th December 2010, 15:57   #36
BHPian
 
Sprucegoose's Avatar
 
Join Date: Jan 2006
Location: Mumbai
Posts: 311
Thanked: 38 Times
Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by pranavt View Post
The Cosworth setup is crap because of the stupid blue flexible pipe. That thing will introduce turbulence into the intake charge which is undesirable unless you want to mix fuel with air.

The rest of the theory is mostly irrelevant because something so basic has been overlooked so badly.




Something similar has already been used on a few Honda motors like the H22, etc
Damnit!!
any idea how effective it was?
Sprucegoose is offline   Reply With Quote
Old 15th December 2010, 18:23   #37
BHPian
 
di1in's Avatar
 
Join Date: Jan 2009
Location: Bnglr&Thrissur
Posts: 384
Thanked: 66 Times
Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by pranavt View Post
The Cosworth setup is crap because of the stupid blue flexible pipe. That thing will introduce turbulence into the intake charge which is undesirable unless you want to mix fuel with air.
I've seen a whole lot of CAIs here at various forums using those flexible plastic piping leading up to the filter. Is it really that bad, considering that from the filter onwards we use a straight pipe with smooth inner lining.
Wouldn't the filter block any turbulence as air filters through it and the flow thus obtained would be smoother right? Or am i missing something..?
di1in is offline   Reply With Quote
Old 15th December 2010, 19:17   #38
CPH
BHPian
 
Join Date: Jan 2010
Location: London
Posts: 577
Thanked: 33 Times
Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by di1in View Post
I've seen a whole lot of CAIs here at various forums using those flexible plastic piping leading up to the filter. Is it really that bad, considering that from the filter onwards we use a straight pipe with smooth inner lining.
Wouldn't the filter block any turbulence as air filters through it and the flow thus obtained would be smoother right? Or am i missing something..?
Turbulences are restrictions. They force the engine to work harder to drag air into the combustion chamber. It does not matter where the turbulences are in the system. Turbulences can even enhance each other depending on where they are. also picking up the air from outside the car can be a point of turbulences as well as a low pressure zone.

@ khoj - I am not impressed by the set up of this cosworth kit.

1st flaw is the pick up point
2nd flaw is the use of convulated pipe
3rd flaw is the filter element
4th flaw is the size of the pipe, which should be smaller at one point between the filter and the throttle body to gain gas speed and therefore torque.

I do not dismiss your claim that it is at the bottom end a bit of an improvement, but then you did not run the car with a new OE filter element (flowing much better than a dirty one) before the fitting of the Cosworth kit.

Re ITG. I am not a fan of them. Recently when ITG designed a revision for the Fiat T-Jet engine, where the customer was under the imprseeion he gained 10bhp at least, the dThis was done together with TMC Motorsport.
CPH is offline   Reply With Quote
Old 15th December 2010, 20:13   #39
Senior - BHPian
 
khoj's Avatar
 
Join Date: Sep 2008
Location: Dilli
Posts: 2,722
Thanked: 1,253 Times
Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by CPH View Post
@ khoj - I am not impressed by the set up of this cosworth kit.

1st flaw is the pick up point
2nd flaw is the use of convulated pipe
3rd flaw is the filter element
4th flaw is the size of the pipe, which should be smaller at one point between the filter and the throttle body to gain gas speed and therefore torque.

I do not dismiss your claim that it is at the bottom end a bit of an improvement, but then you did not run the car with a new OE filter element (flowing much better than a dirty one) before the fitting of the Cosworth kit.
Well let us see what we can do to improve the situation with the kit in place.

Where do you suggest the pick up point should be.
I could remove the plastic pipe and let the air into the filter directly.
I cannot do anything regarding the filter element itself but would like to know what is wrong with the same.
The steel pipe as it comes out of the filter has a dia x and then as it bends upwards towards the engine inlet it increases to x +1/2". This however should result in reduction in velocity of air as it expands over a larger area.

Regarding running the car with a new OE filter, well the CAI went in with the car having run only a couple of thousand kilometers so the filter was fairly clean even if not absolutely new. Anyways the point here is to see what best we can make of the situation. Let me have your views.

Last edited by khoj : 15th December 2010 at 20:14.
khoj is offline   Reply With Quote
Old 16th December 2010, 09:22   #40
BHPian
 
di1in's Avatar
 
Join Date: Jan 2009
Location: Bnglr&Thrissur
Posts: 384
Thanked: 66 Times
Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by CPH View Post
Turbulences are restrictions. They force the engine to work harder to drag air into the combustion chamber. It does not matter where the turbulences are in the system. Turbulences can even enhance each other depending on where they are. also picking up the air from outside the car can be a point of turbulences as well as a low pressure zone.
Got it now.

In the patent below they use a vertically alligned filter on the hood scoop of the vehicle to smoothen turbulence and this better flow is directed towards the actual airfilter.
Hood air scoop - Patent 7794525

So one possible solution for khoj would be to place a similar low restriction filter at the mouth of the CAI and change the flexible hose to one of those mandrel bent metal piping as well.

P.S: The flexible hose seems to have been a DIY method - no wonder it ain't perfect.
di1in is offline   Reply With Quote
Old 16th December 2010, 10:31   #41
CPH
BHPian
 
Join Date: Jan 2010
Location: London
Posts: 577
Thanked: 33 Times
Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by di1in View Post
Got it now.

In the patent below they use a vertically alligned filter on the hood scoop of the vehicle to smoothen turbulence and this better flow is directed towards the actual airfilter.
Hood air scoop - Patent 7794525

So one possible solution for khoj would be to place a similar low restriction filter at the mouth of the CAI and change the flexible hose to one of those mandrel bent metal piping as well.

P.S: The flexible hose seems to have been a DIY method - no wonder it ain't perfect.
I am a big fan of open filter elements. This does not mean that *I categorically reject enclosed filter elements. I use them in some applications, where it is not possible to utilise the benefits of the open filter. In kkoj's application I personally would bin the entire solution by Cosworth and start again with a custumised silicone hose and an open twin cone filter element.

I don't like the use of metal pipes. They suffer from heat soak and they can't vary diameters as needed as easily as silicone hoses. Apart from it they lack the flexibility of silicone, which can become a problem with ageing engine mounts. To counteract it it will be come rather expensive.

You are absolutely right. Flexible hoses are a DIY job and in air intakes are a no-no.
CPH is offline   Reply With Quote
Old 16th December 2010, 12:05   #42
BHPian
 
Join Date: Dec 2009
Location: Sydney
Posts: 46
Thanked: 2 Times
Default Re: Aspects of designing an Air Intake Revision

Good thread guys, and there are alot of answers indicating that a few people here have actually done the research / had a go themselves. I've played alot with intakes over the years with my cars and my opinion after all that play.

Fit a high flow air filter in the standard airbox, remove any resonator boxes that are inline, replace any of that horrible flexi pipe with pipe that is smooth inside and be happy with that result.

Or

Fit aftermarket cams and put the car on a dyno to tune the length of the intake pipe to get an optimum result.

Paulstar is offline   Reply With Quote
Old 16th December 2010, 13:12   #43
BHPian
 
sarmarishi's Avatar
 
Join Date: Oct 2009
Location: Bangalore
Posts: 424
Thanked: 80 Times
Default Re: Aspects of designing an Air Intake Revision

Hi CPH... Gr8 thread. I am posting a picture of my 2005 MPFi Esteem fitted with a K&N performance filter. I think it is the TC 4550. Not too sure will have to check the packaging. anyway I installed it for lower-end torque and was wondering if I should install a CAI. I didnt go in for it as the original piping has the sensor in it and it will need to be taken out and modified. Also, the K&N is exactly in the place that the original filter was in. Next to the filter is a hole in the right fender to draw in cold air from. Is this a correct set-up?
Attached Thumbnails
Aspects of designing an Air Intake Revision-08112009.jpg  

sarmarishi is offline   Reply With Quote
Old 16th December 2010, 18:11   #44
CPH
BHPian
 
Join Date: Jan 2010
Location: London
Posts: 577
Thanked: 33 Times
Default Re: Aspects of designing an Air Intake Revision

Quote:
Originally Posted by sarmarishi View Post
Hi CPH... Gr8 thread. I am posting a picture of my 2005 MPFi Esteem fitted with a K&N performance filter. I think it is the TC 4550. Not too sure will have to check the packaging. anyway I installed it for lower-end torque and was wondering if I should install a CAI. I didnt go in for it as the original piping has the sensor in it and it will need to be taken out and modified. Also, the K&N is exactly in the place that the original filter was in. Next to the filter is a hole in the right fender to draw in cold air from. Is this a correct set-up?
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).
CPH is offline   Reply With Quote
Old 17th December 2010, 11:12   #45
DNS
BHPian
 
DNS's Avatar
 
Join Date: Aug 2009
Location: Mumbai
Posts: 73
Thanked: Once
Default Re: Aspects of designing an Air Intake Revision

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
Attached Thumbnails
Aspects of designing an Air Intake Revision-img00051201007041352.jpg  

Attached Images
 

Last edited by DNS : 17th December 2010 at 11:18. Reason: Needed to indicate position of flexible pipe in the image
DNS is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Air filter and Air intake sunilvarma Technical Stuff 10 4th November 2010 10:58
Alloys + Upsize for Palio MJD - Legal Aspects, Endorsement on RC Book, Insurance Doc anandpadhye Tyre & Alloy wheel Section 9 3rd April 2010 16:27
Diffrence between an ordinary cold air intake and a ram air intake?? Vys De BlUR Technical Stuff 24 1st April 2008 12:59
Best air filter or cold air intake for Skoda RS Kartik9500 Modifications & Accessories 9 7th February 2008 03:43
technical aspects in technical driving ram_hyundai Technical Stuff 1 2nd February 2008 21:12


All times are GMT +5.5. The time now is 02:01.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks