Performance panel filter or CAI? Tell us what you use

[Martin]

On my previous cars i had the following
VXII Coomodore LS1 V8 - HSV Airbox + K&N
Ford Focus XR5 - Simota CAI

On the focus im not really sure if there was any real improvement.

I guess my issue is that most CAI kits for the TSi Motor seem to be a bit on the pricey side (Id be ok with sub 300 bucks for CAI but 925?) I think for the little gains you get its not worth it!

Given how much air volume a V8 can consume I can imagine the CAI did provide an improvement
I also agree it's not worth spending $925 on a CAI for a 2L stock engine
There is a cheap option - the BSH True Seal Intake $200
BSH TSI 2.0T True Seal Intake - BSH Speedshop
It's likely to be pretty noisy and you'll have to see about the frieght/delivery cost
(I'm not sure which one you would use ont he Octavia, Golf MKV or MKVI)

[Weekend-Warrior]

It might only be a 2L, but it's a 2L with a turbocharger bolted to it which increases the effective capacity of the engine.

But if it's for more performance, I'd spend the money on the exhaust first. You're likely to see larger gains, especially on a turbo.

[Martin]

YEah, have to agreed with that

[Antiplastix]

Just go with the standard filter and chuck the noise suppression grate underneath it in the bin. It blocks the air flow by about 50%.

[dArK5HaD0w]

Just go with the standard filter and chuck the noise suppression grate underneath it in the bin. It blocks the air flow by about 50%.

can it b removed?

in my previous car (astra 1. - i removed the "s-bend" inside the airbox, to give it a more straight-ish flow.

[BottomScratcher]

Some of things that always leap out to me, but I seldom see considered when it comes to CAIs and airflow mass are,

1. The greatly variable ambient air intake temp, density, and humidity. Also the altitude at which the tests are conducted. Ask anyone who's ever owned a car with triple Webers about how altitude made it run like a hairy goat at moderate altitudes. And that's moderate Australian altitude. We don't even have any proper mountains. I never see any tests that say "Adjusted to sea level" or "Conducted at ???m above sea level". It might sound like nit picking, but given the minute increases being achieved they could easily be minute decreases in reality were the tests truly scientific, so why not factor the variables into the tests? When it comes to weather, unless otherwise stated, there is no level playing field.

2. The only CAI that I had that was truly a CAI was one I put on a BMW e30 M3 I should've never sold. It was completely encased in an insulated box, so was not exposed to any radiant heat from the engine bay. I haven't seen any other in the last 20 years that is fully insulated from engine bay heat.

3. Ever try to pour a 440ml can of Guinness into a 425ml Schooner glass? It doesn't matter how much you increase the airflow mass through a filter. The throttle body, manifold, valve ports, and cylinder capacities, like the Schooner glass, are a constant. The surface friction across unpolished engine parts is also constant. So the only way to get more air into a combustion chamber is to compress it by turbo or supercharging. Bigger throated throttle bodies, high flow air filters, and the current batch of CAI's are IMHO a WOFTAM.

[Martin]

The webers & altitude are not an issue for fuel injected cars running a closed loop system (sensors),
the fuel is managed/adjusted automatically, Webers can't do that (they only meter fuel/air ratio)

The CAI tests are normally done back to back at the same time & place so that's fine

I do agree CAI's are pretty marginal

[BottomScratcher]

The webers & altitude are not an issue for fuel injected cars running a closed loop system (sensors),
the fuel is managed/adjusted automatically, Webers can't do that (they only meter fuel/air ratio)

Yep, fully agree. I got a bit off track reminiscing. The point of mentioning altitude was the difference it makes to air temp and density.

[Antiplastix]

can it b removed?

in my previous car (astra 1. - i removed the "s-bend" inside the airbox, to give it a more straight-ish flow.

Take the lid off the filter box, remove the filter, underneath the filter is a louvre design restricter. Take it out and toss it.

[Mysticality]

The most air I had ever seen pass through my MAF was 1,050cfm (cubic feet/minute)
With the APR Carbonio, it jumped to 1,293.

Worse off economy-wise when on power, better off economy-wise when on highway. Odd outcome, but there it is.

*sometimes* a K&N panel filter can improve the sound of the intake, like a mate of mine's Mazda3 (Canadian spec) but apart from that I wouldn't bother.
I love my Carbonio... And even better, its cheaper than the TSI one!! At least, cheaper than Martin's. (sorry mate! )

[woofy]

Whats passes by a MAF doesn't equate much to how much is in the cylinder at ignition though. particularly in most cars the MAF is right where the new part is added. It could well mean the car is adding more fuel or less as you have seen, but no more air is actually in reality getting in.

[brad]

Take the lid off the filter box, remove the filter, underneath the filter is a louvre design restricter. Take it out and toss it.

Isn't that grid / louvre there to straighten out turbulent air flow?

[Martin]

The most air I had ever seen pass through my MAF was 1,050cfm (cubic feet/minute)
With the APR Carbonio, it jumped to 1,293.

I can't see any reason to doubt the MAF readings
(I never got a chance to check my before/after MAF readings)
Diesels don't have a throttle butterfly valve, they are regulated via the fuel supply, I wonder how much of a difference this makes

I love my Carbonio... And even better, its cheaper than the TSI one!! At least, cheaper than Martin's. (sorry mate! )

Well, you know, you win some you loose some
At the time I bought the car there was a Carbonio going cheap on the Aus VW Golf forum - I missed it
I also love my Carbonio and remember that adage "quality is remembered long after the price is forgotten"

But I have scored a (fake) carbon engine cover at a good price

[BottomScratcher]

Whats passes by a MAF doesn't equate much to how much is in the cylinder at ignition though. particularly in most cars the MAF is right where the new part is added. It could well mean the car is adding more fuel or less as you have seen, but no more air is actually in reality getting in.

Goes to what I said about the 440ml can of Guinness and the 425ml schooner glass. It doesn't matter how much unpressurized air goes through an intake system. Once the piston is at the bottom of the intake stroke and the valves are closed ready for compression the cylinder capacity dictates how much air is in the cylinder. The only way to get more air into the combustion chamber at ignition is to pressurize the intake air with a turbo or supercharger. Having more air go through the MAF isn't going to increase the volumetric output of a turbo. On naturally aspirated engines the only thing supplying the intake air at ignition is the vacuum in the cylinder created by the downward stroke of the piston. You could unbolt the air filter altogether, put ram tubes on, port and polish the head cavities, valve guides, etc, etc, etc, and you're still not going to get any more air in the chamber once the back pressure limit is reached unless you add a GMC blower.

Unfortunately a lot of guys laugh at the amount of money that women spend on cosmetics that make all sorts of claims about what they do, but then spend lots of money on car accessories that are about as useful as the cosmetics.

[Mysticality]

Unfortunately a lot of guys laugh at the amount of money that women spend on cosmetics that make all sorts of claims about what they do, but then spend lots of money on car accessories that are about as useful as the cosmetics.

My Carbonio sounds great, and so does my 3" catback... If those are the only gains I've gotten from upgrading both ends of piping - then sobeit!
I think I can live with that.
Of course, I'm not speaking for everybody with that piece of text - but I'm sure that it counts for a fair few.