[Sankar]

The airfilter of the i10 Kappa is seriously small. Its smaller than i10 1.1 and Santro and Astar air filters. Why does Hyundai equip this motor with such a small filter?

Pics and stats copied from K&N website. Look at the flow number too (of K&N replacement of course, but will give an idea of how the stock would flow). i10 1.2 filter flows the least.

Do you guys think replacing the stock one with a larger filter would yield better FE?


i10 1.2 Kappa
163.7 cfm @1.5 inH20
Depth: 0.875 in (22 mm)
Length: 10.063 in (256 mm)
Width: 4.063 in (103 mm)



i10 1.1
305.1 cfm @1.5 inH20
Depth: 1.063 in (27 mm)
Length: 9.25 in (235 mm)
Width: 7 in (178 mm)


AStar (Upto 2010)
248.3 cfm @1.5 inH20
Depth: 1.625 in (41 mm)
Length: 9.625 in (244 mm)
Width: 5.75 in (146 mm)

[dhanushs]

Sankar, how is the engine bay space around the air filter?. I think the main reason for a such a design would be space limitations. If not..

Try pluggin in an ODB and drive around with and without the filter. If there is a difference, you will see it.

[Sankar]

There's enough space in there to mount a larger airbox. Don't have an OBD tool with me now, i would've done it otherwise.


The filtered air compartment area of the airbox has a lot of corrugations and ridges, put there as if to strengthen the structure. I wonder how bad these would be affecting the flow. But one good thing is that it traps dust Compared to this my in AStar's airbox (Swifts too) the filtered air compartment is smooth without any such thing. Even the pre filtered area is smooth.

And on top of it, when i opened the airbox is found fine dust after the filter where it shouldn't be The filter is stock. This never happened in AStar with stock paper filter, Cosworth and BMC. Even with BMC which supposedly lets more dust in than paper, the rubber manifold didn't have dust in it when i checked.

Even the air intake tube is weird, its got fur lining. Probably to keep itself warm during winters...hehehe

[Sankar]

The rubber manifold. You can clearly see dust in there. Not good in a regularly serviced 14.5k done car.


The area of the airbox after the filter. Its dusty, i cleaned some, but its still there. Note the structural ridges inside the filter. Why does it have to be there? Astar box didn't have such flow impeding design inside it.


Area before the filter.


The airfilter. Its small.



The fur lined hose.



I temporarily installed BMC filter in the i10. The setup is not permanent, i'm selling the BMC kit.


With the BMC the car is very eager to revv out and is picking up speeds faster once i cross 2.5k RPM. Stock was just the opposite, with better low end response. This is expected.

[bejoy]

Originally Posted by Sankar

Do you guys think replacing the stock one with a larger filter would yield better FE?

It may not better the FE, since the ECU will meter the airflow (or through O2 in exhaust) anyway and maintain the correct air-fuel ratio.

Originally Posted by Sankar

There's enough space in there to mount a larger airbox. Don't have an OBD tool with me now, i would've done it otherwise.


The filtered air compartment area of the airbox has a lot of corrugations and ridges, put there as if to strengthen the structure. I wonder how bad these would be affecting the flow. But one good thing is that it traps dust Compared to this my in AStar's airbox (Swifts too) the filtered air compartment is smooth without any such thing. Even the pre filtered area is smooth.

And on top of it, when i opened the airbox is found fine dust after the filter where it shouldn't be The filter is stock. This never happened in AStar with stock paper filter, Cosworth and BMC. Even with BMC which supposedly lets more dust in than paper, the rubber manifold didn't have dust in it when i checked.

Even the air intake tube is weird, its got fur lining. Probably to keep itself warm during winters...hehehe

Sankar, does the filter sits in the box with its edges sealed tight? If there is slight gap along the edges, the dust can leak through.

Again, from the pictures though the filter size is small, it looks like the surface area of the actual filter is more. i.e. the height seems to be more.

In case of K&N stock replacement filter, the flow rate might be lower, since their design seems to be uniform across different models. I mean the overall filter height is same for all. Therefore, in this case, K&N might give a lesser flow than the stock filter.

[Sankar]

Yes the filter sits there with the edges sealed. If it doesn't sit right the box wouldn't close, i have tried. The dust was even found on the inner side of the filter.

I agree that the depth of the filter is more, but its not too deep compared to my AStar's filter. The exact height difference i will measure when i get both out again. Surface area of the Suzuki filter is still larger.

The depth (height) of K&N filters are not the same across the range. You can verify this from their filter technical specifications given at their website. Incidentally the stock replacement filter for AStar (9-10 and Swift 1.2) filter is deeper than the one for i10 1.2.

i10 1.2
33-2977 - K&N Replacement Filters, Replacement Air Filter
AStar
33-2968 - K&N Replacement Filters, Replacement Air Filter
i10 1.1
33-2978 - K&N Replacement Filters, Replacement Air Filter
i20 (1.2 and 1.4)
33-2960 - K&N Replacement Filters, Replacement Air Filter

[Sankar]

Tried out the CDA in the i10 1.2 and this time made the connection at the manifold more secure using a correct spacer. I didn't have the right spacer with me when i tried it out before so had to use some duct tape windings to make the dia larger, it wasn't nice at all.

Anyways the Kappa is performing better now, the engine has lost a bit of its low end torque but not bad enough to affect drive-ability and it can still pull from crawling speeds in 2nd gear cleanly. More importantly the engine revs out eagerly and doesn't feel stifled when reaching higher RPM.

If i decide to retain this setup, i will get 90 degree silicone hose, reducers and duct to make it permanent. The Silicone bend will replace the OE manifold (and resonator box) and should improve things further since it will flow better than the OE manifold which has some internal ridges.

[suhaas307]

It's great to see that you're a hands-on kind of guy, Sankar. Very few would actually take the trouble and understand the mechanical components of their cars.

Anyway, the actual surface area of the stock filter seems to be much larger, so you needn't be worried, really. Companies don't always provide performance based components in their products. Moreover, stock filters differ from car to car. Although I'd expect the 3-pot mill in the A-Star to be equipped with a smaller filter. But guess such intricacies are best left to the engineers to deal with.

The BMC filter should improve performance. Especially when coupled with a CAI.

[Sankar]

Originally Posted by suhaas307

Anyway, the actual surface area of the stock filter seems to be much larger, so you needn't be worried, really.

The area of the stock filter is smaller compared to that of Santro's and i10 IRDe's.

Its not larger than CDA's either, CDA being a cotton element would flow more compared to paper anyways. I can't now do a filter to filter comparison photo since BMC is installed, but the following pics would give an idea. The red marking is til where the element is inside CDA. If i were to cut out the paper element and make it into a cylinder like BMC it still would be much smaller.




Why did the engineers thought it would be better to leave the innards of the airbox with ridges and valleys where it would hurt airflow instead of making it smooth, atleast on the engine side? Engineers are made to compromise by other teams, so its not always the best. The ridges/valleys are not even in the direction of the flow, its perpendicular to it. One can assume how this would flow compared to a smoother box. I have seen other airboxes, motorcycles and other cars, but never one like this.

[bejoy]

Originally Posted by Sankar

Anyways the Kappa is performing better now, the engine has lost a bit of its low end torque but not bad enough to affect drive-ability and it can still pull from crawling speeds in 2nd gear cleanly. More importantly the engine revs out eagerly and doesn't feel stifled when reaching higher RPM.Attachment 827214

Sankar, I would have expected to improve the low end torque. Hope you did an ECU reset after changing the filter.

I checked my i10's filter today. Its small too and though the surface area is more, most of the air is pulled from the filter folds and once this gets dusty, the overall flow will get affected.

[Sankar]

Originally Posted by bejoy

Sankar, I would have expected to improve the low end torque. Hope you did an ECU reset after changing the filter.

The low end in the i10 was such that it used to jump the moment clutch is dropped, and with a little input from the throttle it used to shoot off. Keep on giving the throttle and soon after the revs would feel like its not climbing fast enough. Now with the BMC the tendency to do the initial jump has reduced and power delivery has become more linear overall. The low end is still there and still very use-able but more linear.

Yes disconnected the battery post installation.


Anyone know where the IAT sensor is in i10 1.2? Is it a part of TB? Coz didn't see one in the manifold.

[ankur_fox]

Has anyone tried to clean the air filter by themselves for the i10? Could you provide some insight on how this is done? I have read a few posts, but since this discussion is based on the i10, the advise would be much more focused.

I have the stock filter installed, never thought of changing it thought it may be a good idea.

[dhanushs]

Originally Posted by ankur_fox

Has anyone tried to clean the air filter by themselves for the i10? Could you provide some insight on how this is done? I have read a few posts, but since this discussion is based on the i10, the advise would be much more focused.

I have the stock filter installed, never thought of changing it thought it may be a good idea.

Just use a vacuum cleaner to clean it. On the long run, replacing might be mandatory.

[dhawcash]

i10 1.2 Kappa
163.7 cfm @1.5 inH20
Depth: 0.875 in (22 mm)
Length: 10.063 in (256 mm)
Width: 4.063 in (103 mm)



i10 1.1
305.1 cfm @1.5 inH20
Depth: 1.063 in (27 mm)
Length: 9.25 in (235 mm)
Width: 7 in (178 mm)


AStar (Upto 2010)
248.3 cfm @1.5 inH20
Depth: 1.625 in (41 mm)
Length: 9.625 in (244 mm)
Width: 5.75 in (146 mm)

Hello Sir,
Just curious, How did you get hold of the flow figures? Do you have access to a flow bench? if yes it must have needed different adapters to measure each filter's flow (as the size is different)?

[aaggoswami]

I am not sure if this thinking of mine is correct or not, but a smaller air filter is opted in favor of low end response. i10 does have enough space to have a long intake for better torque, the only way to obtain turbulence is let the air pass through small intake, which would create some turbulence as the engine is big for the filter.

This theory is applicable only for bumper to bumper traffic. Otherwise, if the CFM values are to be believed, the engine might need more air, which is visible from the dust inside the air hoses. Certainly not good. But I think, even Baleno has a small air filter, considering sheer swept volume ( and not output ).