Cased on you experiences and knowledge......Which do you guys recommend..and also which is the best downpipe to fit a magnex backbox.....anyone know the combined power gains?

 

A Japanese STI panel filter is definately the best.

 

Didn't somebody on here test one recently on an air flow testing unit and found it to be upto 10% more restrictive than an OE paper one I have a JR Racing which I'm more than happy with, but K&N and Green Cotton are as highly thought of in general on here. As my JR is a lifetime unit, I'll never have the need to try and see if the STi is any better, and as they are a serviceable item I won't bother costwise either.

 

I can say that the STi panel filter definately isnt anywhere near as restrictive as the oem filter, better breathing up top and more bhp and torque on my JDM STi

(12bhp and 15lbs of torque!)

Tony

 

http://bbs.scoobynet.co.uk/showthrea...ght=sti+filter

It was a report in Scoobymag

 

Really? Did that come out on the dyno sheet? Yours was a jdm sti...mines is a uk spec wagon. What about downpipes to fit a magnex backbox? Any ideas?

 

I'm not saying a word about filters!

A down-pipe doesn't fit to the backbox. It fits to the centre section. Is that a Magnex? Is it the 2.5" Magnex centre section too?

There isn't a 'best' so to speak. If you want quality, then go for a full stainless pipe, which is TIG welded too such as the Hayward and Scott one. The Magnex twin dump has a mild steel flange, but it's cheap.

Whether you choose open-necked, closed neck, sports cat, titanium is a matter of choice and budget.

You really need to match one to your modifications for the best results. But power gains/losses vary from car to car. Take the WR1 for example - put a decat on them and they lose power.

You could always enter the competition (and hope to win) in the next issue of that Subaru magazine - what do they call it now?

 

Filter results (please leave them as links):

www.scoobymagazine.com/images/af_standard.jpg
www.scoobymagazine.com/images/af_green.jpg
www.scoobymagazine.com/images/af_sti.jpg

 

Thanks.....I have to say that im a little confused now, though, since I got the car with the magnex backbox, Im not even sure if it is from the centre section or not. Firstly I'd have to find that out.... then I'd know if I also needed the centre section or not. I just wondered if already having a magnex backbox would be a limiting factor ie if I had to get a specific downpipe to fit it etc. I think the presence of the Magnex is an advantage as it sounds great and I dont have to pay for another backbox! Any idea of the price for the downpipe and centre section?

 

 

Lol....Now theres' crystal clarity!! All I need to do now is determine my current setup and plan accordingly....

 

Was the car cooled down between pulls? It seems to me that those pulls were taken one after the other with very little time in-between. The car would have been really hot by the time the STi filter was fitted and as we know, intake and exhaust temp, really affects boost/fuel/timing mapping on these cars.

Aren't these results a little meaningless? The car would have been compensating and protecting itself from high temps by reducing it's power output.

The last pull would have been the lowest (which coincides with the STi filter going in) anyway.

 

I have a MY05 STI PPP - is the standard filter on this the one you are all on about ? I spoke to the dealer on Saturday and they said if I fitted a Green or K&N oiled Panel filter it would invalidate my warranty and probably bugger the MAF !! Do subaru (UK) do a better filter for the Type UK STI that I could buy for better performance ?

 

Got a Jap STi panel filter in mine together with Vortex backbox on my 05 Sti PPP.

Very happy.

 

No ! The standard filter is just like any other paper disposable for any other marque, similar to what you'd buy at Halfords. The STi one is better made, but is still a disposable paper style. You're dealer is speaking half truths about the oiled filters. ITG filters were reknowned for killing MAF's due to their overoiliness, but I have never heard of K&N, JR Racing or Green doing this. Much of this scaremongering started around the 98-00 cars, due to the extreme sensitivity of their MAF's but all cars prior and since have been fine using anything except ITG. However, you dealer is completely correct to say that an aftermarket filter may invalidate your warranty in the event of a claim, but as you can change it back in under 2 minutes, who cares.

 

The scoobymag test was done on a wrx and not an STi, heat soak could have played a big part in lower performance.....
The test on my MY03 JDM STi was done at 1700 miles on a rolling road, 2 runs before with the oem filter, 2 runs after with the STi panel filter, the results were within a few mins of each other, the car was still on the rolling road when the filter was changed, the difference was 12bhp and 15lbs of torque gain now im not saying every car will get gains like these, but you will get an improvement somewhere, and yes, these are a service item, they need changing every 2 years/20k miles, which isnt really that bad considering its a dry performance filter.

Tony

 

Heat wasn't an issue.

Order of test: (See times on the printouts)

Standard (old)
Standard (new)
STI (new)
Standard) - repeat
STi (new) - repeat
Green (new)

 

You should be able to bolt almost anything on

 

Right cheers highlander68k, I must admit though due to the mixed opinions and me being a novice, Im realy confused about filters.....there seems to be almost no consensus:which is the main criteria for using a product.......Arrghh!!

 

Thanks for the info. Can I get this STI filter from a Dealer ? if not, where can I order it from ? and how much is it ?