The definitive "What Air Filter?" discussion thread

[bananawhip 0]

Anyone tried a new BMC OTA yet?

 

I really like the look of them but it's a space saving idea, I would've thought the normally CDA makes a bit more power surely?

 

Sold my BMC recently and fitted a Simota Carbon Fibre Aero Form kit, absolutely love it! Was a pig to fit but god damn it's a lot of fun and looks extremely cool. I'll get a pic up as it's a new one on this thread.

[Kevin Bacon 5]

Anyone tried a new BMC OTA yet?

 

I really like the look of them but it's a space saving idea, I would've thought the normally CDA makes a bit more power surely?

 

Dunno, but I'm not paying £250 to find out :D

 

Sold my BMC recently and fitted a Simota Carbon Fibre Aero Form kit, absolutely love it! Was a pig to fit but god damn it's a lot of fun and looks extremely cool. I'll get a pic up as it's a new one on this thread.

 

Yeah so did I as I've gone back to the standard air box, with paper filter :D

 

Do you mean this Simota kit? -

http://www.simota.com/main.htm?pid=23&F ... rod_ID=158

[bananawhip 0]

Dunno, but I'm not paying £250 to find out

 

Yeah right, somebody else can have a go with it at that price

 

Do you mean this Simota kit? -

 

Yep that's exactly the one Kev, just fancied something different and if I'm honest I'm very impressed. I think its a little less restrictive then the BMC but still pretty well heat shielded, makes all the right noises and feels a bit more lively, be interesting to get it on the rollers

 

Still a massive fan of the BMC though don't get me wrong

[Kevin Bacon 5]

Cool, sounds intriguing. I wouldn't mind seeing a pic of it installed in your car :D

 

The BMC works great on a standard-ish VR6. IMO, on modified ones, they can cause a restriction at the top end.

[bananawhip 0]

The BMC works great on a standard-ish VR6. IMO, on modified ones, they can cause a restriction at the top end.

 

That would explain it, as I've mentioned before mines had a fair bit of work for an NA and maybe the BMC wasn't supplying the extra air flow I needed, I'll get a pic up when I get a chance

[Wompa 0]

Okey... What is the different between a K&N 57i kit and a ordinary K&N Filter?

 

Is it the flexitube that is the different? :confused4:

 

If so, then I can just buy a filter for 40£ and then a flexitube and still have money for a Bonrath Powerrohr :lol:

[strimmer 0]

Well another great read, here I am looking for any info on my air filter as I'm selling it.

 

My 2p to the thread

 

On my 1.8 16V stock engine I have the Pipercross PK223, at the other end of airflow the engine is helped to breath mated to a 4 branch manifold and as the exhaust is a tad excessive :eek: I've never noticed how loud the air filter roars. But what might be of interest, or not :lol: , I rollong roaded the beast to 149bhp, maybe that is of no surprise to some, I was bowled over but I'm easily pleased! Perhaps its the combination of air filter and manifold/exhaust or does the exhaust/manifold take all the credit for the up in power from standard, I don't know? :wave:

[eugopnosaj 0]

Man reading all this has confused the hell outta me! :lol:

 

I currently drive a 2l 16V and need to replace my filter (obviously) but wasn't quite sure which one to go for and now im even more confused. Ideally more power would be the best option and im not 'too' bothered by extra added noise.

 

Theres lots of info regarding various different setups for the VR, less for the G60 and as i can't use a cone filter on the valver im limited to using the existing box etc.

 

Does drilling it actually improve performance or does it just add excess noise?

 

Should i use say a K & N filter with an extended cold air feed (run a pipe down near the lower grilles in the bumper/in front of the main grill infront of rad)

 

Thanks!

[Kevin Bacon 5]

All drilling does is ruin an otherwise perfectly good (and expensive) air box :D

 

We've all done it though, and convinced ourselves the extra noise = extra power, but it doesn't.

 

If the engine is standard, it really doesn't need anything other than what VW put in the airbox at the factory. The whole induction path, from air box inlet to intake valve is carefully optimised to give the best torque / noise / airflow compromise.

 

Highly modified engines might benefit from a free flow filter, but even then you're not talking a huge amount in terms of power gains. The filter itself isn't actually the restrictive parts of an intake system. If you picked apart a standard paper filter and laid all the pleats out on the floor, you'd almost have a small rug, which is a massive filtration surface area. Do the same to a K&N and there's barely enough material to make a flannel with, which is why when K&Ns get blocked with dust, you lose flow very quickly. Paper blocks easily too as it traps finer dust, but it can continue to flow enough air due it's surface area.

 

Airboxes and MAF sensors tend to be the main restrictions, but in the case of the air box, it's usually a deliberate restriction by using 2 Helmholtz resonators (aka snorkels) to fine tune the low rpm torque and reduce induction roar. Not all restrictions are bad :D

[eugopnosaj 0]

Hmmm still slightly confused :lol: at the moment the engine is standard however i am going to change the cams from 9a to KR with probably a KR head too and various other performance improvements and im looking into possible forced induction but not for a while (till i get the required parts).

 

Do you reckon for the time being (or even with the KR cams) that a standard, cheapish (i think around £9 from ECP) paper filter will do the trick or will the cams benefit from a more expensive K & N. I dont plan on drilling the box as you say, its pointless as it ruins the box and creates excessive noise

[twofourten 0]

I have no tech knowledge at all really, but have really enjoyed this thread - good read

I also have to say that the Simota kit does look great (i'm a sucker for aesthetics) & i'd love to see one fitted in a Rado

 

I'm driving a G60 with standard at the moment and will be getting a BBM Howitzer (with heat sheild) Intake System w/adapter for stock G60 chargers fitted along with my new clutch on 20th April - I'll let you know if there is any power difference/sound change etc...

 

FYI: SWG do a kit that looks like the standard one and takes paper filters - http://www.swgmotorsport.com/asps/ShowD ... asp?id=172

I emailed them to check... Thanks to StormchargedVR6 for pointing these out to me...

[greasegriff 0]

Stumbled across this thread but it has made me think. I've got the VR6 going into Stealth later in the month to have a Vortech V9 fitted (plus Schrick, cams and a re-map). I currently have a BMC-CDA fitted but from what I've read, this may not be the best as it may let dust into the 'charger which I gather isn't ideal!

 

Any opinions and recommendations on a replacement (if required at all?)

[Wompa 0]

If I can get ahold of a original air box for the VR6... How the sound going to be like?

 

Thinking of using K&N filter and drill the box.. I want a nice deep sound!

[6cylinder 0]

Will be loud with a k+n with a drilled airbox.

I have a standard airfilter in mine with the bottom corner missing and a 3.5 inch cold air feed going up to it from the lower part of my bumper acting as a cold air feed.

Seems to pick up a bit better mid rpm and howls at 4000 rpm. 8)

[Wompa 0]

MHMH! Nice, thanks mate! Then I know what to aim for...

 

But how good will the original box be if I start to modify the engine? Thinking of cams and something more.. no real hardcore parts but just for the extra push.

[CazzaVR 0]

The original box will be fine! Have a look at Kev's engine bay in his sig above- standard airbox with turbo etc running big power 8) The VR makes a nice noise with just the snorkel removed- no need to drill!

[Kevin Bacon 5]

Cheers chap :D

 

Absolutely, there is nothing wrong with the stock air box, even when running a big turbo :D

So long as you leave it alone, don't drill it, don't take the snorkel off (helmholtz resonator) etc, then it will work perfectly. Even with a paper filter 8)

 

If you're just after some noise, then yeah, carefully unclip the snorkel, or swiss cheese the lower half, or a cone filter will work :D

[Jim 1]

I feel sort of ashamed to say it but I pulled out my airbox on the VR the other day with the intention of just trying it without the snorkel fitted (to see what it sounded like) - but couldn't see how it unclipped. It seemed almost like it was "part" of the airbox (like plastic glued to plastic) and that I'd basically have to cut it out - which I didn't want to do.

 

Should it just pull out?

[CazzaVR 0]

It's a very snug fit and slots onto some 'runners'. Tap it out of the airbox with a hammer ;)

[Jim 1]

Ahh.. okey doke.

 

I know the one on the G60 was easy to remove - that did just unclip and slide out. Will have another look this evening possibly then :)

[big ben 10]

i could do with a better filter for my VRT, but think its just a universal cone thing shoved on :lol:

[Kevin Bacon 5]

yeah it's just a tight fit Jim as said already, but it does come out. Don't chop it out or bin it etc, just in case! New airboxes cost £100, and they're not obsolete weirdly. Maybe VW have kept some back in case people get fed up with induction roar :lol:

 

There is also a front snorkel you can remove, aswell as the plastic air guide that sits behind the headlight.

 

I did a lot of testing comparing cones, BMC and the stock box in various states of choppedness and snorkelessness and I came to the conclusion (3 airboxes later) that how VW did it in the first place is best :D

[coullstar 0]

Thats good to know as I was thinking of trying a standard airbox on mine.

[jamminvr6storm 0]

Here is a pic of my air filter, next to my bread bin so you can get a sense of scale :lol:

 

 

I was tempted to use a stock air box but I have a 4" intake pipe

[Kevin Bacon 5]

I think with the power you're making, that size air filter is appropriate :lol: