Air

[zei20t]

When replacing the airbox with an aftermarket, or in my case a DIY airbox, how do you go about replacing the maf tunnel, and the part after the maf with the two metal clips?

Can that section alone be bought somewhere? As I don't want to hack it out of the stock box, I would rather keep it together to put back on when I sell the car

Golf Mk5 and Golf R use the TFSI engine so best place would be to check out those sections for ideas. Unfortunately my TSI has a slightly different intake

[wfdTamar]

If you intend selling the car after a few years any butchering of the engine bay will affect resale big time. How about a K&N filer in the standard box?

[MountainBikeMike]

If you intend selling the car after a few years any butchering of the engine bay will affect resale big time. How about a K&N filer in the standard box?

Done. Not enough difference

[PsychoPuppie]

69-9756TFK - K&N 69 Series Typhoon Kits, Performance Intake Kit direct from K&N

for similar money to the apr intake you can get one of these. are they worth it?

[Martin]

Man, that's a total rip off (and illegal - can't have an open filter, it has to be in a box)

If you want a CAI and are prepared to spend that sort of money get the APR one, at least you get pretty carbon

I don't believe you will realise any tangible performance gains with a CAI
Car air boxes are designed to reduce intake noise while still flowing air very well
(The air intake and filter have very little to do with emissions issues)

See my sig - I have the APR CAI and the stage II carbon intake tube
Benefits are limited to:

• Makes the engine bay look cool
• Cool intake noises
• Never have to replace the air filter but I do have to clean the K&N filter from time to time

After not replacing the air filter 25 times/years the CAI will start saving me money

[woofy]

I find K & N filters are a placebo effect or very little gains on dynos if its already a high power engine like the RS has. I had one for years in previous cars, and cleaning was a PITA, it's an artform not to overload the oil and make sure the thing is dry first, and even though I didn't have any issues I'm aware of, fouling the MAF sensors isn't worth it over just chucking and putting a new filter in. If someone was really anal, just put them in more often, they are cheap.

I think it all comes down to the sound really.

[dArK5HaD0w]

I don't believe you will realise any tangible performance gains with a CAI
Car air boxes are designed to reduce intake noise while still flowing air very well
(The air intake and filter have very little to do with emissions issues)

See my sig - I have the APR CAI and the stage II carbon intake tube
Benefits are limited to:

• Makes the engine bay look cool
• Cool intake noises
• Never have to replace the air filter but I do have to clean the K&N filter from time to time

exactly the reason why i have not gone down the aftermarket CAI path.

it was the same advice i got from the guys at the garage. they've been installing various performance products on the VAG family for many many years.

the gains r so so minor, that there is no need to re tune/map the ecu.

[BottomScratcher]

I don't care what anyone wants to spend their money on. If it makes you happy do it. A CAI might sound and look cool, but I can't see it "smoothing" the air flow in a closed system when every other restriction in the system remains the same. Likewise oversize throttle bodies and such. Without port and polishing the head and valve guides, the inside of the intake manifold, etc, etc, etc, to me it's like putting 300mm of 18mm hose on the end of 30m of 12mm garden hose and expecting to get more water through the hose in the same amount of time.

I don't want to start a blue about it. Like I said, if it floats your boat do it, but in a closed system with a fixed (i.e. constant) combustion cylinder capacity, and a pressure determined by a turbo I just don't see how a CAI gets around Boyle's Law. I don't dipute that air flow from the intake of a CAI to the outlet of the CAI is 30-35% higher than stock, but I don't see all of that "extra" air getting to the cylinder. I just see greater backpressure in the filter box, because the volume of the rest of the system remains the same. There are ways of engineering more air into cylinders, but fitting a CAI on its own without mapping and other extensive mods isn't one of them.

EDIT: Doing extensive intake mods and leaving the exhaust stock is a WOFTAM as well.

[gldgti]

There is a thread in the diesels section about this topic that has some good posts.

To give my brief opinion - the factory setup is very good, I wouldn't waste money on anything else until I was pushing 350-400hp.

Cold air and aftermarket intakes are a great way for people to make money selling parts to car enthusiasts with minimal expense and risk to themselves.

Then again, if you like the look and the noiz, go nuts

with respect to the 'smoothing' airflow comment - the MAF grid is designed to do just that - it tries to create a quasy laminar flow zone for the MAF so that the airflow readings are accurate. Doing this actually restricts the flow a bit, as laminar flow is not the most efficient way to get air through a pipe - but, the benefits of an accurate maf reading outweigh the restriction.

If you modify the intake before the maf significantly enough to get more air through, then the maf calibration will be off.

If you want more air through the pipe, you want turbulent flow, and this would be the opposite of 'smooth'. It would also not be what the maf needs for an accurate flow measurement.

[PsychoPuppie]

these are the posts that i was wanting when i posted this thread.
its so hard to read b'ween all the marketing and fancy looks to see what is actually worth upgrading on your car.
thank you for your input.