Stock AirBox Vs Bmc Cda

[BrunoSbc]

Hi there,

Need some help to understand why my mod doesn't work.

I have,


Forge Dump Valve FMFSITVR

034 MotorSport Test Pipe 3"

Audi A6 3.0 Tfsi Ignition Coils Rev E

Ngk Iridium Ix bkr7eix

Catch Can Bsh Stage 2

Treadstone Tr6 Ic


Since i don't like any off the intakes available for our car i decide to adapt one Bmc Cda Sp-14 for the S3.

Originally i have stock air box with kn filter and it makes 266hp/400nm.

With Bmc cda installed like this pic:




Made 250hp/390nm!!!



Then i read that the maf should not be too close to turbo,so changed to this:





Made 256hp/394nm!!!



In the two installations i used some Black Silicone Ducting pushing the air from the low front end off the car.




Any advices why the car isn't doing at least the same power that stock air box with kn filter does?


Position off the maf?



Best Regards and sorry my bad English.

[xander3zero]

Most likely b/c the stock airbox is very effective and doesn't need any modification or upgrade in these cars

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[AudiTFSI3o3]

Can you actually confirm those numbers?



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[BrunoSbc]

I have dynoed the car with both modifications,that's the only way that i have to confirm the values.

If i switch back to the stock intake with kn the 266hp comes back again.

[CorneliusRox]

Sounds like an easy fix is to stay with the stock setup. Air temp might be the biggest factor here.

[Operator]

Unless you are actually pulling air from a lower spot ( out of the heated engine bay) a SRI won't be too help full. Maybe try some heat shielding.

[Jake@JHM]

Where all of these done on the same day around the same time? If not there is your answer. Dynos are highly unreliable and there are so many different variables that will alter the results. Did you know lightweight wheels will give you more HP on the dyno? The temperature.. the DA ..how heat soaked the car was before the pull.. it all impacts the results.

[rongeur]

Another reason could be that the stock airbox pulls fresh air from the grille and from the fender which is a greater "straw" than your single silicone hose intake.
Log your g/sec and I bet you will see difference in air mass between the setups.
The proper upgrade (forge) uses a twintake setup iirc

[BrunoSbc]

@ Operator,the air is coming from the front end off the car,in the last picture the red circule is were the air is entering by the silicone ducting.


@ Jake@JHM both tests were done im the same day,first stock air box (266hp) then mod 1 Bad values (250hp) then mounted stock and values were back (266hp)

Another day...Dynoed stock first (266hp),mount the new way off bmc with maf distance from turbo incresead and bad values again (256hp).Better than the first way it was mounted but still not the results i expected.


@ rongeur i have done some logs just to see,the results:

There is some g/s diference,but no power!?

Stock airbox kn filter:



-------------------------------------------------------------------

Bmc Cda Like the second pic:

[ultraleggera a4]

I have a few question, did you try to reset the ECU, if not the car did not have time to adapt to all that extra g/s. Also was that 266 to the wheels or crank because if that is to the wheels that is beyond impressive. That is hands down the highest g/s I have seen on a k03 was the a fan blowing straight into it, the highest I have hit is 220g/s.

[LoKisSpYdR]

I've hit low 220s a few times.

It is very odd that you are pushing more air and have lower numbers, especially when AFRs are identical.
This has got to be crank. I don't think the k03 can support 260awhp.

[BrunoSbc]

@ ultraleggera a4 what do you mean by " reset the ecu " ? The 266hp is at the crank.At the wheels would be very nice hehe

@ LoKisSpYdR thats the problem,more air but less power!?i keep searching an answer.Maybe the position off the maf,don't now what to think but don't wanna quite so easy

[martin0079]

The problem is the bend after the maf it is screwing up the maf readings I ran into this issue before but mine was bad enough to pull a lean code

[kvitrafn]

But if you compare lambda the BMC values don't seem much off. Or does a slight leaning like 0,77ish to 0,73ish as roughly observed here add this much power? I'm Revo myself but I haven't tried to lean out the mixture yet.

Also, this is a lot more air from something that supposedly not a worthwhile mod to this car. Are you saying the MAF is reading incorrectly? The lambda does seem more rich as I suppose it would be if the MAF is reading artificially high values.

[rongeur]

Those are great MAF numbers 230's! I revoke my comment about it being restrictive compared to the BMC inline filter
THe BMC runs 5 degrees hotter in the higher RPMs.

I may have missed it, what tune are you running?

[BrunoSbc]

@ martin0079 have you done custom intake too?you solved your problem by removing the bend after the maf?

@ kvitrafn that's exactly what i think,this mod add's lot of air,i think that it's only missing something to it work like it should.

@ rongeur i'm running some custom tune from one of the best programers in portugal " Mbpower ".The day that i did the log with the bmc was hotter than the day i did with the stock intake,maybe that's the reason for the 5 degrees hotter.