[Sankar]

Originally Posted by dipdawiz

Without much expectation on performance (FE should not fall) want to install cold air intake in my 2010 Ritz Zxi. Finishing the extended warranty mid of this year. So want to celebrate 4th year completion with this installation . Expecting a smoother revvy engine and little bit growl.

Either Cosworth or BMC. Want to know

- Which one would be preferable and why?

BMC. Better build (for their carbon models) and better design (for their DIA, CDA, OTA models). If you buy the DIA, use both ears on the filter cover body to support/secure the filter assy.

If you're looking at something like the Cosworth CAI which has a conical filter at the end of steel pipe, any respectable brands would be fine, my in filter material would be cotton sandwich like K&N/Green/BMC because they last really long and work very well if oiled right.

Originally Posted by deathwalkr

The outer shell of the DIA broke and been running the setup as a conical setup and never really felt any big difference.

Only issue would be during car wash or heavy rains i guess...

Is the outer shell only cracked? If its just cracked its fixable. Without the outer cover intake air temps would be high if the filter is inside the engine bay and not sealed separately, once the radiator fan kicks in IAT will shoot up by 5 to 6 degrees C in a very short span of time and this would happen frequently in city drives. It must be performing good now, but there is scope for improvement. Its ideal to get the outer cover fixed and use the duct to suck in fresh air.

[dipdawiz]

Originally Posted by Sankar

BMC. Better build (for their carbon models) and better design (for their DIA, CDA, OTA models). If you buy the DIA, use both ears on the filter cover body to support/secure the filter assy.

Thanks Sankar. In case of open conical filters, how much the risk for the filter/engine as it is open? As someone said heavy rain/wash etc etc. anything specific to take care in different situations?

Any one from Bangalore can let me know any reliable seller and installer for BMC as well as any Cosworth type CAI?

[Sankar]

Originally Posted by dipdawiz

Thanks Sankar. In case of open conical filters, how much the risk for the filter/engine as it is open? As someone said heavy rain/wash etc etc. anything specific to take care in different situations?

Open conical filters will require more frequent checks and cleanings than an enclosed type conical filters as the filter element is exposed to more dust inside the engine bay.
Open filters if placed inside the engine bay without outside air feed and separation/partitioning will suck in hot air which is not good for performance.
With open filters you need to be careful not to wet the filter when engine bay is being washed which some places do as part of water service.
Open filters makes a peculiar suction noise, some like it but i don't.
Good custom open filter installation kits usually come with partitions and air feeds etc to get most of the colder outside air to the filter and to the engine.
Most of the "open filter at the end of a short pipe" type of conical filter is good for sound, and open hood dyno pulls. The more you drive more the performance goes down as the air entering the engine gets hotter.

[deathwalkr]

Post above sums it all Sankar you could add in the cost difference between the two as well.

[dipdawiz]

Originally Posted by Sankar

Open conical filters will require more frequent checks and cleanings than an enclosed type conical filters as the filter element is exposed to more dust inside the engine bay.
Open filters if placed inside the engine bay without outside air feed and separation/partitioning will suck in hot air which is not good for performance.

Thanks Sankar for your input. I have gone through your post on BMC CDA in A-Star. There you mentioned low end torque is hampered. I would not like to loose the low end torque K12 engine produces. Is there any specific reason to loose low end due to CDA? Is there any option to overcome it?

[Sankar]

Originally Posted by deathwalkr

Post above sums it all Sankar you could add in the cost difference between the two as well.

Too many options in the market for each type, both are available in the range from cheap to expensive.

Originally Posted by dipdawiz

Thanks Sankar for your input. I have gone through your post on BMC CDA in A-Star. There you mentioned low end torque is hampered. I would not like to loose the low end torque K12 engine produces. Is there any specific reason to loose low end due to CDA? Is there any option to overcome it?

Yes, there was a reduction in low end torque, but that was fixed by inserting a 10cm long pipe between the the CDA and the rubber inlet manifold. The K12B engine doesn't seem to lose much low end torque with the BMC OTA (never tried the CDA because that was sold long before). I have been using a BMC OTA with the Swift directly connected to the inlet manifold rubber without any extra length in between, but inserting the pipe should give bit more torque.

[aayushnair]

Originally Posted by Sankar

The more you drive more the performance goes down as the air entering the engine gets hotter.

Hi Sankar,

Just a reflection on your quote, Wouldnt there be more cooler air coming into the engine bay when you drive more?
If this doesnt happen the engine would get over-killed with high temps if you drive more.

I'm only saying that this can be true in a stand-still situation where the air-intake is only sucking in hot air from the engine bay, but once you move on and drive, the cars cooling system will suck in air from outside the bay, automatically cooling the interiors.

So the performance of a car using an open filter would suffer only during stand-still situations or bumper to bumper traffic scenarios (that too dependent on air feed it gets)

Cheers
Aayush

[Sankar]

Originally Posted by aayushnair

Hi Sankar,

Just a reflection on your quote, Wouldnt there be more cooler air coming into the engine bay when you drive more?
If this doesnt happen the engine would get over-killed with high temps if you drive more.

I'm only saying that this can be true in a stand-still situation where the air-intake is only sucking in hot air from the engine bay, but once you move on and drive, the cars cooling system will suck in air from outside the bay, automatically cooling the interiors.

So the performance of a car using an open filter would suffer only during stand-still situations or bumper to bumper traffic scenarios (that too dependent on air feed it gets)

Cheers
Aayush

No, even while the car is on the move on open highways engine bay stays hot, but not as hot as when driving through city roads or when at standstill. But the air getting into the airfilter is hot enough to lower the performance. If in doubt hook up on OBD scan tool and read the intake air temperatures when driving with stock box, enclosed air filter with "proper" external air feed, and an open filter or enclosed filter left in the engine bay with duct removed.

Engine radiates huge amounts of heat when its running - from the block, the head and the catalytic converter runs even still hotter further adding to the heat. While on the move some of this heat is carried away by air that gets into the engine bay from the front. But there is a catch! Most of the air that gets into the engine bay has already passed through the AC condenser (cooling you) and the radiator (cooling the engine) and that air is hot! Air is not at ambient temperature anymore when it enters the engine bay.

If you look at the front air dam/bumper of any modern car you can see that behind the grill is mostly blocked with openings only for radiator/condenser and an air inlet for the air filter box (airbox); or in some cases a cutout through which air can stream in to an airbox inlet pipe. Rest of the grill area is blocked in order to enhance aerodynamic efficiency and to channel maximum amount of air through the radiator for efficient cooling of the engine and the scoop/cutout for the airbox. A full open mesh grill with the blocking pieces of plastic removed from behind probably will reduce the engine bay temps (but may reduce radiator efficiency), but that will hurt the aerodynamic efficiency of the car when doing highway speeds.

Unless its an air-cooled engine its that radiator and the airflow through the radiator that makes sure that the engine doesn't get killed by heat when driven more.

Using an open filter in the engine while at standstill or while moving will let the engine suck in hot air only.

[aayushnair]

Thanks Sankar, this clears a lot of questions and doubts i had about this too!

Cheers,
Aayush.