Performance panel filter or CAI? Tell us what you use

[andymarc]

Just wanted to ask people out there what they use.
Also a discussion to is there really any benefit on CAI as apposed to a hi end Panel filter

[Dutch77]

Realise this is for Octavia but closely related. In the process of looking at CAIs at the moment and will be going that route over a replacement filter.

An interesting test series was conducted in the USA on the golfmk6 forum comparing stock to filter to CAI.. obviously other factors can impact these results but interesting all the same.

Technical Understanding: Intakes: Stock vs. Drop In vs. Aftermarket - VW GTI MKVI Forum / VW Golf R Forum / VW Golf MKVI Forum / VW GTI Forum - Golfmk6.com

[Ryan_R]

Nice read

I've added a K&N reusable filter (although I've not checked if it's still there since my most recent service) and there's hardly any noticeable difference - probably more of a placebo. I never tested fuel economy differences.

[woofy]

I had K & N in my 323 Sports Edition and it did make a difference both in driving and at the dyno....but would not bother with the RS as they were an art to clean properly and you always wonder whether the oil fouls up sensors etc.

[brad]

neither

have tried a few oiled panel filters in the past (PiperCross & FinerFilter) and neither made any noticeable difference. I've read enough about the OEM filter & airbox to believe it is efficient enough for the amount of power these cars have.

I would be tempted to try a non-oiled cone filter if I could get something like a twintake.

I also believe that if you could get more cold air into the OEM box it would be an improvement too.

[woofy]

I'm kinda over the whole change the intake thing, most CAIs or SRIs seem to just be more pain than gain and depending on how low you put them, seem to suck up water and hydrolock more often than not. Unless you live in Tassie, most of the time the road temps are hot here so moving the intake away from the engine bay doesn't really help a lot. A dyno run won't accurately show the effect of hot road temps either as the car is sitting under cover, half the time in A/C.

[Dutch77]

That contradicts the findings in the US testing I linked above which definitely showed improvements with a well designed CAI over the stock system - ie. one which is sucking in outside air.

Maybe not in extra power generated, my take was it was more about improving power across the rev range. They were certainly critical of the stock design which was about reducing noise more than anything.

However not trying to claim the US test is right, just one possible take on things - I'm certainly no expert, just like gathering multiple points of view and learn more about my car.

[brad]

Fair enough. Keep in mind they have already introduced other variables & upped the power.

[Dutch77]

From other threads I gathered that just a swap from stock to an aftermarket filter/CAI would not be worthwhile - you'd want a tune done to take this into account.. then it seemed like there were additional benefits in doing this mod.

[woofy]

Again the scientist in me, says that unless there is a way to measure power in our hot conditions, a dyno with a 10% change might not even be noticable (apart from the placebo air induction sound). I would like to see some dyno tests done outside. The amount of cars I have seen over the years that knocked out a lower fog light or run these into the wheel well, all well and good if you have ice on the road, but when you put an air intake that low right near some hot tarmac it would be better off up at bonnet height. Dynos aren't at ground level either. Air restriction for noise is another thing altogether though, if you remove that, then sometimes you can see a difference, but if the engine isn't starving for oxygen, you can allow as much in as you like but there isn't going to be big difference.

As above, to see benefits for pretty much anything you need to change a few things that work together and retune it to take advantage of it. The default program will allow for small changes and possibly output a bit more, but it was made to run at the factory specs with the factory equipment in place. At one stage I was looking at the Oettinger stage 1 and 2 packages which had the intakes combined with the tune to suit them. When the work is already done for you it makes it a lot easier.

[Martin]

I agree there are improvements, but they are very small
Where these small improvements become more important/noticeable is when you have modified the engine to produce more power

If you are keeping the ECU/Engine/Exhaust stock I would not waste money on a high end CAI (panel filter - yeah sure)

I updated my Octavia VRS TSI ECU to ECU stage one - the top end was worse than stock
It ran out of puff in the 5500~6000 rpm range and took a long time to rev out after that
While I have no evidence as to why this was happening,
looking a the review Dutch77 has posted, the CAI has improved MAF and boost control
(Although, the boost control with Carbonio Stage 1 looks worse that stock over 6400 rpm! Make sure you get the full kit)

To get around this I was short shifting and driving off the large torque increase that Stage1 gives
But ultimately I decided to do something about this...
I got the big exhaust down pipe, StageII ECU update and full Carbonio kit
(The difference between ECU Stage I and II is small - Stage II came as part of the exhaust upgrade package)
This totally addressed the issue and made me very happy
The engine now revs out to redline without dragging it's heals
The guys at the shop were very impressed,
they rang me to say the work was complete and "your car goes like hell now"
They even had the professional customer care to tell me to watch out in the wet
as they expected it to torque steer all over the place (it does, change driving style in the wet)

The downside for some will the noise from the CAI
During normal driving is not much different
When you open the throttle you will get whistle noises, intake noise and diverter valve noise
I also get more noise from the large exhaust down pipe
These are all modern turbo noises, not wonderful in my view (not like old style Webers and Camshaft noises)

[Weekend-Warrior]

I updated my Octavia VRS TSI ECU to ECU stage one - the top end was worse than stock
It ran out of puff in the 5500~6000 rpm range and took a long time to rev out after that
While I have no evidence as to why this was happening,

I can guess what was happening. With the intake and tune power was being delivered sooner, however it hit a wall higher in the rev range due to the restriction of the exhaust. You said it had more torque which also support this.

With the new exhaust and free flowing intake, the new tune could make the most out of your current set up.

The limiting factor now is probably either the intercooler, turbo or fuel system or a combination. Not sure what these are all rated to.

A free flowing intake will make a difference, whether you can feel it with the seat of the pants dynometer, not sure.

On our other car I bolted on a cat back exhaust just for a better sound and it made just over 10% more power atw. This power is all higher in the rev range so hard to notice on the street. The noise on the other hand...

These are all modern turbo noises, not wonderful in my view (not like old style Webers and Camshaft noises)

Agree, webbers and lumpy cams sound great, but you can't switch between tunes quite as easily when it starts raining and the cold start can be an issue.

[andymarc]

Im in two minds as to what im going to do...
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!

[Martin]

I can guess what was happening. With the intake and tune power was being delivered sooner, however it hit a wall higher in the rev range due to the restriction of the exhaust. You said it had more torque which also support this.

With the new exhaust and free flowing intake, the new tune could make the most out of your current set up.

The limiting factor now is probably either the intercooler, turbo or fuel system or a combination.

Yes - that is a nice summary completely in line with what I think is going on

The TSI fuel delivery is solid (unlike the TFSI)
I won't be chasing any more power, it's got heaps

Agree, webbers and lumpy cams sound great, but you can't switch between tunes quite as easily when it starts raining and the cold start can be an issue.

Fully agree, the wonderful thing about a turbo charged car is the fuel savings off the throttle versus performance on throttle, much wider fuel and power range than a normally aspirated car

[Dutch77]

Interesting.. I used to be in the Commodore brigade as well.

In isolation I think yes, a waste of cash, but team it up with a tune and you'll start to see some gains. I think the APR Carbonio is in the 500s, but might need the other bits and pieces? Viezu are doing their VARDesign CAIs with tunes at very good prices.. probably works out to less than 500 in a package.