I have been running an ITG for a few thousand miles now and thought I would see if it needed cleaning. I found the sticky oil all over the airbox (only the intake side) so gave it a good wiping. I thought I would revert to the standard filter for a while and see if there was any noticable difference. Here are my findings:

1. It is quieter

2. I appear to have gained some low down torque (below 3000 RPM).

3. Above 3000 RPM the engine is definately less keen to rev freely.

Now some questions:

1. Can other people verify the above

2. Is the standard, paper, filter not in fashion as its performance drops off as it gets dirty - might not be a problem for low mileage users or the fact that it is changed every 2 years / 30,000 miles.

3. Has anybody actually been on a rolling road before and after just a filter change (to RAMAIR or ITG)?

4. Is there a likelyhood of the oil getting through the filter as has been reported with the Ramairs?

Thanks,

.Richard

 

Interesting. Are the original filter and the ITG the only things that have been on the car (i.e., you didn't have a Ramair on there or anything?)

TIA

-= mike =-

 

Never used a Ramair (I was put off by the stories of too much gunk). ITG had just been recommended as an option.
I forgot to mention I am running a S/Sport back box but no other mods.
Having seem the gunk still in the bottom of the filter box with the ITG I was beginning to wonder if the same promlems as the Ramair were likely to occur.

.Richard

 

I was advised by Power Engineering to remove my ITG on the basis that it could contaminate the airflow sensor. The inside of the airbox was gunky (I saw this for myself) and PE said that they had to clean some of the crud off the sensor hotwire (although I didn't inspect it myself beforehand).

Pete@ScoobySport dismissed this, saying that the ITG is much less soggy than the Ramair and there's no way surplus polymer was going to get pulled out of it. He suggested that the residue in my airbox was left over from the Ramair filter that I had previously. Sorry to say this Pete, but from Richard's experiences it looks like PE were right.

I'd suggest a Blitz induction kit if you can handle the noise (personally I love it). They're a damn sight easier to maintain than polymer panel filters, too. You just undo the jubilee clip and blow it out from the inside with an airline.

-= mike =-

 

I've had my ITG for 4000 miles and no gunk so far. It is probably best to wipe off any excess surface oil from new foam filters before installation.

 

Well it looks like David and I will have to disagree on this one (first time for everything).

You can wring out an ITG and nothing will come out of it.

They come in a sealed plastic bag and there is no polymer residue in the bag. By comparison, the last batch of Ramair filters we saw were swimming in green gunk, in their bags.

With regard to AMS contamination, only MY99 and STi5 cars have the film sensors. All earlier cars were hot wire, which is less sensitive, but more robust. Subaru UK's recommended filter for the hot wire AMS is the (heavily oiled) Ramair.

Scoobysport have supplied nearly 500 ITG filters, since March, and they have not caused one AMS failure that we know of. Several of these cars have already done 30,000 miles on their ITG's.

Before recommending a filter, we look at quality of construction, performance, life and filtration qualities. The ITG is the only filter that meets all of our requirements.

 

Incidentally, is it true that the MY00 has no MAF sensor of any kind ?

In which case even the oily ramair would be fine ?

 

Pete - I don't like saying anything that could be construed as "negative" in a public forum, but it does seem to me that a wider survey is merited here.

I know you say that the filter seems dry when you remove it from the pack, but it's not a very scientific test. Moving large volumes of air across a viscous fluid is bound move it along to some extent, but will do so very slowly. Just because there is no apparent excess on the foam, that doesn't rule out some seepage.

OTOH Orville reports that his airbox is untarnished so it's obviously not a problem that affects everyone.

In the end I was given one opinion by an experienced person that I respect (you) and a conflicting opinion by another experienced person that I respect (DP). I suppose it was the evidence of my own eyes coupled with Richard Hardaker's comment that caused me to say something here. I hope you can respect my reasons - I'm just trying to further the understanding (mine and others') of the technical issues involved. Anyway, I've had my say on this one and I'll shut up now.

-= mike =-

 

Hi guys...

I'm not getting involved.... or picking sides...

But remember the oil breathers return back into the air intake system...after the filter....

So.. in theory... if oil was blown back... perhaps over a period of time... it could form in the bottom of the box.... thats how the oil gets into the intake system...

Check for yourself...remove the MAF/AFM...rub your finger inside the intake.. chances are you will find traces of oil...

Just thought....

One thing is for sure.. RamAir are pooh...

J.

 

just a note, has anyone tried a K&N filter?

Also i have lots of experiance with uprated cossie engines, if you go over 1 BAR boost presure on those you need a seperate oil breather system to stop the air filter box filling with oil, is the scooby the same problem?

Also if you give the car much more than 3000 rpm on uprated boost when cold the air box fills with green oily ****, bill gwynne could tell you about this known issue.

 

I have a K&N filter panel fitted to a UK '99 Scoob.

I check the air box every time I clean the car. So far, there have been no probs.
Performance has improved.

Thanks

Sonu

 

Have got MY99 with PPP. interested in changing filter, but not intrested in buggaring up car!! - Ramair seems a no-no, and from this thread ITG seems to have problems - any others that are 'approved'?

 

Hi Gary

Can I make it perfectly clear that there never has been a problem with the ITG, on any Impreza, 93-98 or the 99's with the new foil air mass sensor.

ITG designed this filter for the 99 car.

If Mike N did have any gunk on his AMS, I suspect it was from the Ramair that he used for nearly a year, before switching to ITG.

There are over 500 owners using ITG and several of these have done over 30,000 miles since it was fitted. There have been no AMS failures or filters deforming.

When deciding on a filter, the things to consider are...

Construction quality (must not deform)
Reliability (filter and AMS)
Filtration qualities ( to less than 10 microns)
Performance
Life expectancy
Noise (some like it, some don't)

Consider all of these points, but not necessarily in that order.

 

I can only report on what I have found. I am not saying that any 'gunk' has found its way past the filter - the sensor looks clean and there is no residue around the intake pipe. The filter is a quality piece of kit.
I had 'gunk' in the bottom half of the filter box. I asked a friend of mine to check his and he also had a small pool in the bottom. This is definately from the filter. The bag my filter came in was just sticky with no residue in.
As a final note - after running with the standard filter for a week now my ITG is going back in - you do notice the performance drop on boost.

.Richard

 

Sod filters!
Get an induction kit.
More power, less hassle.
Nuff said!

Stef.
(And nobody reply like a little girl saying 'they're too noisy'!!)

 

Richard,

Is that a perform drop on boost with the Standard Filter (clean) or the ITG???

Thanks
Mark

 

Dicky Hardaker is correct, after examining my ITG filter ,there is gunk in the air box....... but only a small amount and none has passed thro' the filter to the airfow sensor. As Pete correctly states the ITG has not 10 pints of the slime floating round the bag that the RamAir has, but would suggest a small amount of the polymer drips down when the car gets really hot.Having said that it has caught and stuck together the odd bit of leaf etc so it's not all that worrying!!

 

Mark,

I meant the performance on boost is better with the ITG filter - hence I am putting it back in.
.Richard

 

Thanks Pete - (ready to open can of worms) how much for an ITG for MY99? and is it self fit or a prof job?