nik52wrx

I have just done a search on panel filters to see if a replacement for the standard STI unit is worth it, unfortunately i'm still unsure.
Opinions seem to vary regarding oil content and effects they have etc.
I was thinking along the lines of a green filter but stumbled across a K&N filter on Revolutions web site claiming that the K&N filter doesn't invalidate your warranty.
Anyone shed any light on this claim as i thought it would invalidate the warranty.
Also, anyone got a green filter and do you have any comments, positive or negative.
Nik.

pippyrips

i'm on my 2nd uprated STI filter

mgcvk

I've had greens for nearly 30,000 miles. No issues. You will hear a bit more induction noise as it is less restrictive.

BigAl024

I have a STi one fitted. No probs so far <touches wood>, but not noticed a massive difference TBH.

davedipster

I had my car serviced at extreme scoobs last time, and they use green filters. It's been fine, sounds abit louder but no quicker at all.

dipster

ARM-Scooby

there was a post about this a few months back where a subaru dealer was selling replacement panel filters by K&N and stating that it wouldnt invalidate your warranty, but mike wood said that wasnt true!

car is set up for the standard one, so should perform well with it.

jasonius

iTrader: (1)

GB on green panel filter runnning at monent iirc..

harvey

iTrader: (48)

As regards warranty, check with Subaru and K+N.
Regardless of what they say, I cannot see that a change of filter will make any difference unless you have a MAF Sensor issue and the dealer claims this is down to crap filtration.
there are some crap filters out there that do not filter down to small microns and this is a BAD thing.

I tried some pannel filters and was so surprised by the results I repeated the experiment on the rollers at Steve Simpson Motorsport the following day and got the same results. Some "experts" were doubtful but Mike Wood came on and said my results were broadly in line with their findings.
I was happy to learn that Prodrive were doing the job right too.

From memory, without finding the thread, I tested four pannel filters.
The difference between the best and worst was only circa 2 BHP.
The "best" was the HKS Green Spounge but that also appeared to have the least filtration letting through the largest particles.
Next with same results was either the O/E Subaru or K+N. Nothing in it and both good at filtering down to small size.
Last was the "STi" which also had good filtration but was also disposable.
As there was only 2 bhp difference and the results were consistent, my conclusion was that it mattered little whether you ran an O/E, K+N or "STi" but because the K+N was re-usable, it probably represented best value for money.
Claims of pannel filters adding 5-10 bhp on a standard car are poppycock.

At the same time I planned to do a well known Scooby Power Mod by removing the inner wing snorkle. From memory this lost 9 bhp and altered fueling.
My conclusion here was that this was just another Scooby Myth, exploded and on a car with an O/E ECU this mod was a NO NO, probably a NO NO on any Scooby running a MAF Sensor and further work would be needed to determine if there were any advantages on a car without MAF Sensor and mappable ECU.

None of the above would have been possible without the use of an accurate, repeatable rolling road.