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Have a query regarding Direct Air Intake.
What is the difference between DAI(Direct Air Intake) and CAI (Cold Air Intake).?
Has any BHPian tried it on a diesel car?
Cosworth supplies with an import specifically for skoda fabia 1.4 Tdi, has any one tried it.?
Does any other supplier provide it specifically for 1.4Tdi engines?
Help me out here as i'm thinking of putting one for my car making it accelerate a bit faster.

https://www.youtube.com/watch?v=xwNtjKT_1cA

A very important Video by Mighty Car Mods. As most of the indian cars are having naturally aspirated engines, adding a CAI (Cold Air Intake) does make a difference to the power gains. So i am going ahead with the Cosworth CAI, and will keep you posted.
Regards
Keep Revvin'

No, think about this really carefully.

You engine burns a mixture of super heated air and Diesel fuel injected at super high presssure.

The air entering your engine has passed through an air filter, a turbo (which is really hot) and an intercooller where it was coolled down to increase it's density.

It was then sent into the cylinder, via an induction system, where it was squashed a lot and heated to almost 700 Deg C before the Diesel fuel was injected. The fuel was added in about 300 seperate pulses of the injectors - the first few heated the cylinder some more, the next big mass of pulses made the super heat that makes the power stroke, and then a few extra pulses were added to clean up the exhaust gasses a little.

The spent air then leaves the engine via the exhaust system, and some of it is used to spool the turbo for the next boost, but a lot of it is just sent into the exhaust - bypassing the turbo if the pressure is too high - in old fashion speak a "Dump Valve" is used to release extra pressure.

Your act of adding a CAI will cool the initial temp by probably 1-2 Deg C - so little a change that the ECU won't even notice it. And by the time the air has been through the turbo and the intercooller the difference will be 0.1 Deg C +/- which is too little to be detected even by NASA let alone an ECU.

In short you are buying noise, nothing else.

No - Again think carefully. The air entering an NA engine passes through the air filter, and then into the standard induction system - throttle (in a petrol engine), FI system, manifolds etc. Anything you add with a CAI is negated by the time the air actually enters the engine including temps. A lot of ECUs don't even measure air density anyway, only airflow.

The VVT / VTEC systems in modern engines are not actually there to add power - they are there to make really powerful engines more flexible. How else can Honda make a 198hp 1.6 4 cyl usable ? (Civic Type R)

Also remember the S2000 is a full on performance machine, the engine is actually detuned for the road to make it acceptible in terms of driveability for the road - so any de-restriction is going to show a gain.

Mighty car mods also tested CAIs on other cars - the result was, if anything, worse.

If you think I am wrong then please prove it - get a CAI and measure the intake temps the ECU sees (accessible via the OBDII port) ABA - After / Before / After. I think you won't see any difference at all. The Scangauge, Ultragauge etc. give you these values.

I had installed CAI in my stock Ford ikon 1.6 Nxt.
Without CAI - slow after 160kmph to reach 190kmph.
With CAI - speedo touches 200kmph without any lag from 160kmph.

I have installed Stock replacement K&N filter in my Polo 1.6 GT Tdi.
Without K&N - slow after 160kmph to reach 200kmph.
With K&N - speedo touches 200kmph without much lag from 160kmph.

These after market Air filters makes a difference in TOP END only.
If you are not interested in TOP end then these are waste of money.

I am looking for both, high end and also low end power so that i don't have to change gears in constantly in traffic. Cosworth claims that it will provide power at low ends also. Some one has to try it first, so i'm taking the heat :)

Have ordered the CAI already clap: so will let you know the results and i am hoping for some power gains. Will keep you posted for the improvements. Dyno testing will be done, but after putting a free flow exhaust.

You have to first dyno stock car and dyno after mods as well to know the exact difference.

It seems this user is banned but for info a standard Polo 1.4 TDI (either the 75 or 80hp model) can be remapped to 100hp quite easily. They can both make this power whilst retaining the standard air filter and exhaust system - they just have the extra performance available - as quietly and as smoothly as before.

Do you have a dyno figure for each of these cars ? I fitted a K&N panel replacement to my Aygo and it did seem slightly better at full-on rpm but nothing startling.

No, Usually we don't dyno for just k&n filter addition.

Is your Aygo Petrol/Diesel?
Is is remapped?

So really your claims are subjective - "it felt better" - just like mine.

My Aygo was petrol and not remapped - that would be a waste of money and time.

No, To find any performance mods gains we usually drag with our friends car to find the difference instead of spending 3-4k for dynos.

Which is kind of the same thing, maybe ? :D

I tried something similar with my Aygo - changed filters and then videoed the performance of the car between two points in the same gear and foot flat down several times with each type of filter.

None of them showed any real change, and a CAI showed nothing at all.

I have no idea about your Aygo, It has shown performance increase in our cars Period.

Hello All,

Has anyone tried to swap the exhaust with a turbo-back straight pipes (cat-delete, resonator-delete) ?
I'm planning to do this on my swift (D). I've seen a lot of people from europe do this on their VW's and mercs.

Sorry, not convinced - but that doesn't matter.

:deadhorse

Is your car remapped ? If not start there.

Mine is remapped by Tune-O-Tronics. Max power map. According to Vivek from T-O-T, there is still some juice left (a little more power based map).