Hi all,

currently have a MY03 STi and I am picking up my new 05 STi next Tuesday. I currently have a Afterburner Vortex Backbox and STi panel filter on my non PPP car that I would like to switch onto my new PPP'd STi.

I have heard that such mods could cause a problem with the performance of the car and are not reccommended.

I have also heard that the engine management is adaptive and would benifit from the freer breathing.

So....

has anyone got any positive or negative opinions on the above based on experience, or just good old technical knowledge of new age STi's.

Cheers,

Dan

 

Wouldn't that affect your warranty?

 

when I put the deposit down, they agreed to fit it for me saying no problem at all with warranty. Now the technicians are saying they can't be seen to be fitting non-Prodrive exhaust. Sales guy has said they think it will hamper performance but he can't understand why. So i'll fit it myself depending on the opinions of this thread.

A backbox is easy to fit anyway.... 10min job.

 

I'm sorry I can't help with your question.

However - being new around here - if you want to fit an STI panel filter, what is in the STI as standard?

Cheers

Guy

 

Just a paper cheapo one. Not as free flowing. Apparantly......

 

Hmmm sounds good - I can feel the need for further investigation into this also.

 

For the hassle, leave it as supplied and flog the other bits.

The STI panel filter will not be popular with any warranty claim, as any messing with the filtration tends to get people up in arms. The MAF (which tells the ECU how much air is flowing, hence controlling fuelling) is sensitive to changes to the filtration/air flow/... You've got a brand new car, I'd leave it well alone. Besides, performance will *not* be affected by this.

The backbox will not affect performance in any significant manner, just make more noise.


None of the mods will do anything for the car other than void a bit of the warranty; there's no performance to be had from a back box or filter. I'd leave the car as standard whilst you've got your warranty, sell the bits on here, and spend the cash on having fun . Or a few tanks of petrol

As for the "just a paper cheapo" comment. I can magically fold a paper one out of handmade parchment rolled on virgin's thighs, write STI on the side very neatly in crayon and flog it to you for 100 quid - would that make you happier? . The original is designed to flow more than enough air for the car, and filter to the appropriate levels, so what more do you want from a filter?

 

Yes it would with exhaust or any old filter. but may not if you use the STi Filter. IIRC

I know some peeps have had problems

The explanation below is in layman terms (maynot be "Technically" correct) but I understood it.

As no 2 engines and Boost valves etc. aren't the same

PPP is "TEK2" or "off the peg" stlye. it will have a "Window or limits" for Peak boost and boost spike protection. If you Car is running at the low end of the range and you fit these bits you may see performance gains but if your at the Top end you will get problems of boost spikes or overboost. The ECU then limit boost trying to keep it within the Range and effectively slowing your Car down.

IMHO

Tony

 

On my non PPP 03 STi the backbox alone made little difference except noise. But oh what a noise.

However once the filter was replaced it definitely pulls slightly harder and revs much more freely at the top end.

Purely my opinion on my car.

 

Hi chiark

I've just done a search on the STI panel filter.

It seems that quite a few people(over 30) took part in a group buy on here last year on the basis that they were better than the standard ones - by better it seems that it is claimed they can increase power by up to 5hp and allow a better throttle response.

Are you saying this isn't the case through experience.

Cheers

Guy

 

I know an sti can make an extra 8 bhp, when a standard filter was replaced with an sti one.
Don't subaru garages sell sti panel filters anyway??

 

Re: Group buy, are you 100% sure they were'nt for the older style STi's. Do a search in drivetrain and you'll see that changing air filter to a more flowing one is'nt a good idea on newer >MY01 cars.

 

Thanks I will - although there were a number of 03STI owners buying.

 

Right had a good read of a thread in Drivetrain about filters.

Conclusion was....................makes little or no difference.

This was supported by Mr Wood !!!

 

Sorry, but Chiark's hit the nail on the head.

To be honest, I can't see the point of modding a PPP'd UK car and writing off your warranty.

Josh

 

untill the craving hits you as a tsl 333 car overtakes you and you have to have it!!!!!!!

 

tsl use green filters but there was a recent article in scoobymag re filters-no real difference but i know a lot of people swear by improvements using the sti panel filter!
martin

 

I agree with everyone on here There is no piont frsking losing Warranty for Indution or exhaust "Sound"

Buy a AP22 meter or a Rolling road Day prior to a Mod and check before and after. You will find it may sound like it's got more Power but effectively the Car is far slower.

IMHO

Tony

 

IIRC there was also a feature on this in the first edition of Scoobymagazine. If memory serves, they compared the same car on a rolling road with the standard filter, the STi panel one and the Green Cotton filter. The car's power and torque outputs were lower with the Sti panel filter than with the standard one, The Green Cotton one produced the best results. However, the difference between all three only amounted to a few bhp and ft lbs.

Personally, I'd leave the standard one alson. ts not as if the car isn't going to be quick enough already!

 

Well, Bob Rawle recommends Sti panel filters for new age STis.

I fitted a Sti panel filter and Vortex Afterburner BB to my 02 STi.

Before the changes with a PE sports cat exhaust system and PE remap it gave 308hp and 293 lbft. After the above changes plus a Bob Rawle remap it gave 314 hp and 285 lbft, but peak boost was increased by 0.1 bar to 1.55 bar. On the road the increase in performance was very noticeable after the remap (but not before) and certainly felt alot more than from an increase of 8hp.

My conclusions are that you will need a remap to obtain any noticeable benefits and that rolling roads do not reflect on road performance due to the lower loads which affect boost.

Alan