[Guest]

I've been told (admittedly by the chap who was selling it) that an Apex induction kit would be just the job for my otherwise bog standard evo1. But I thought I'd ask the esteemed gentlemen (and ladies) of the MLR before I cough up any dough. I'm not expecting any great increase in power but ditching the standard filter is something I do on all of my cars. While I'm at it could anyone recommend a good exhaust system as it's got the standard mitsi system on it. Ta.

 

[Guest]

White1,
I've got an Apex'i air filter on my Evo 6 and haven't had any problems with it whatsoever. The only thing I would say is that when you fit it, make sure you feed it with some cold air from the front of the car. I run a piece of ventilation ducting from the front of the car (which isn't ideal but it'll do for now), otherwise the filter will have the oppurtunity to suck in hot underbonnet air and this will reduce the performance increase you gain by having a lower pressure drop in the intake system.

If you can't feed it with cold air then you'd be better off going for a replacement, freer flowing standard panel filter and keeping the original airbox setup.

Hope this helps

Andy

 

[Guest]

I've got one too. Before I bought it I put a similar thread on here and the replies came back very positive for the Apexi!

Steve

 

[Guest]

Have a look at www.gtrowner.com/induction.html
I use a apexi and have no probs.
Chris

 

[Guest]

Every 2-3 months somebody drags up the above induction test review. I must save my response so I can cut and paste it!

This test really p###es me off. It is badly done and the methodology is poor. To start with, using a vacuum cleaner provides too much suction. In the case of the HKS filter, the flow is so high that it actually sucks the oil out of the filter. You can see this in the picture as the oil has soaked the filter paper and smudged the result. You can also see the same effect with the other wet filter. To be valid, the test should have been done with controlled and measured flows. In addition, they should have done a control test, with no contaminant, so as to see if the wet filters were being sucked dry!

The next problem with the test is the dust used and the way they appear to introduce it. IMO, this is only relevent for those who choose the drive through a volcanic dust cloud! It would have been a better test if they had measured the size of particle that was stopped by the filter or not stopped, as the case might be. Then it would be possible to see if the filter is fit for purpose.

Finally, I quote from the page

It is questionable how accurate the original source of data is, as HKS are proven to sell more induction kits than any one of the others featured in the test, and yet there induction kit rates as the worst kit in the test. This suggests that either HKS rely upon their brand name to sell their 'poorly' manufactured air filters, or that the original Japanese test was nothing more than a PR stunt to promote the lesser known equipment. HKS and Blitz continue to be the best selling induction kits in the UK, and are used by Middlehursts, Hiteq and Abbey Motorsport as their first choice when the induction kit modification is carried out

Thats the end of my rant. All 4 filters tested are very good and under normal use will perform equally as well. I think that it is a case of personal preference based on looks!

 

[Guest]

I disagree!! Not all filters are very good. Over the last years I have had experience with all of them. Forget the HKS and Blitz: they let way to many particles through. The Apexi and the K and amp; N work very well. We use the Apexi on our Evo 7 in the 24-h race on the Nürburgring this weekend. Our main competitor, Ralliart Germany, uses a K and amp; N.

It has nothing to do with looks! Who cares about that?!? Filters have to filter!

 

[Guest]

Simon,
I've also got my response from the induction kit report copied so it's easy for me to comment........

Andy

This test is fundamentally flawed in the method of testing. The use of a vacuum cleaner will provide a far greater 'suck' on the filters than that which would be experienced when installed and so it is an unfair test. Due to the possibility of the foam filters 'unloading' under a higher differential pressure (see below for an explanation), these will show up worst on this type of test (as this proves). The fact that some of the filters are coated with oil to improve their filtration properties means that under the high vacuum, the oil will be sucked straight through the filter and onto the filter paper behind.

As far as filtration performance vs power gained goes, my comments are as follows:
The degree of filtration will vary depending upon the method of manufacture and the design of the filter. The airflow through the filter will depend less upon the design and manufacture but more upon the amount of 'free space' that the filter has. As an example, you could have a filter with a single large hole that flows the same amount of air as a similar sized filter filled with lots of little holes. The filtration performance will obviously be different but the airflow through them (and therefore the power gain) will be the same.

Also a filter that is made from a sponge and requires an oil coating to help stick particles to it will, when it starts to get blocked, open up the pores of the filter (due to the differential pressure across it) and this may lead to large deposits of dirt unloading into the air stream. This is a common problem with filters of this type in most of the industries I've worked with filters in. They are OK when they are only lightly loaded with dirt but if they do start to get blocked then you may be in trouble.

The other type are the paper type which are generally of a fixed pore size that won't move around under a high differential pressure. This type tend to offer a better degree of filtration (**provided that they are sized correctly**) but when they block, you will notice a drop off in power because the car can't get enough air through the filter. As a result these filters will tend to have a shorter lifespan than the foam filters.
The main advantage of the foam filters is that they are very easy to clean by washing but you have to be careful that you don't damage them in any way. The best method of cleaning a paper type filter is to blow air backwards through the filter i.e. from the side that is nromally connected to the intake and remove the dust from the outside.

Andy Fox
Ex- Filtration Technical Support Engineer