After MOT next month I am going for a decat downpipe and maybe up pipe to finish off exhaust system.

Also interested in an induction kit. At least I think thats what I want. I want my baby to roar into life.

Not really sure what the difference is though with changing the filter e.g. panel filter and a full induction kit (other than price)?

Don't want any MAF problems etc either as I am a crap mechanic!

Cheers

Matt

MY98 UK Turbo

 

The MAF sensor will be fine on your car.

It's only the later 99-00 cars that have probs and even standard ones blow so I think people over-react a bit about MAF sensitivity and induction kits.

My mate has run a Blitz SUS on a MY00 for 2 years and never blown a MAF.

Basically, induction kit will get air in more freely. All the big power cars have induction kits. Panel filter is better if you want to keep the car fairly standard looking. Only disadvantage of an induction kit is in standing traffic it drags warmer air in from under the bonnet making the car a bit sluggish on set off, but once you are moving this difference goes.

Get an induction kit. They make a cool noise too.
I have a Blitz SUS (very low and easy maintainance) on a 97 car with an MRT high flow inlet pipe. Induction noise is awesome. Sounds like you could suck pedestrians off the kerb.

Mail me if you want more details/pics etc.

Cheers

Rich

 

Thanks for the reply Rich.

YHM

Matt

 

If you remove the resonator a decent panel filter will be good for 300 BHP at least in my humble non scientificly proven opinion

 

Jay

I will have a decat downpipe(brand not yet decided), scoobysport decat centre and scoobysport b/box.

Surely that + a panel filter on a uk 98 car (208/215bhp?) cant get near 300bhp?!

Matt

 

Probably not, but whose to say you won't stop there?

My reason behind my statemant BTW is that the APS cold air induction kit is, in effect a K+N filter stuck in the wing then pipework to get it to the MAF. Its quite well regarded on here and rightly so.

With the resonator removed and a K+N panel filter used basically you've got air drawn from the wing through to the filter then onto the MAF. Bit like the APS but the filtration is in the middle rather than at the start.

Granted a panel may not flow as well as a cone and laminar airflow may be a factor, but not for 300 BHP surely?

Your thoughts anyone

 

Many other cars get way over 300bhp without an induction kit. What's the difference between a flat filter and a flat filter turned round on itself to make a cylinder? Not a lot
The restriction is at the inlet before the filter (the pipework is a tad on the small side ) although it is a 'cold air' feed, then there's the ridiculous resonator contraption. Removing the resonator helps quite a bit. Don't know what could be done about enlarging the actual air inlet cross-section, but presumably something can be knocked out... although it's probably cheaper - and certainly a lot easier - to just fit an induction kit!
Probably why so many people do

[Edited by nom - 4/4/2003 1:10:00 PM]

 

I mistook the reference to resonator as being the cat. So the resonator is part of the breathing gear near the air filter? Sorry - new at this

Jay: I wasnt meaning to claim the I expect to get 300bhp. My replay was following up on yours: -

>>>If you remove the resonator a decent panel filter will be good for 300 BHP at least in my humble non scientificly proven opinion <<<

Did you mean an extra 30bhp as a result of this mod?

Cheers

Matt

 

There's a resonator in the air inlet system as well as in the exhaust system - does the same sort of thing - quietens it all down.
The standard air inlet system is the same as the standard exhaust system - somewhat restrictive - the reason why the engine can't produce the power it could do if the restrictions weren't there. However, the air inlet system is less restrictive than the exhaust system (it has a potential to allow the engine to produce more power under the correct conditions than the standard exhaust system). Allow the air to flow much more easily (eg through an induction kit) while still using the standard exhaust, etc. & there will be almost no improvement in power. However, once the exhaust is changed for a more free-flowing one, the restriction can become the air inlet system. If the engine is in a state of tune that can make use of the additional airflow a replacement induction system would allow (typically running higher than standard boost), then there can be a power gain. If the engine is in a state of tune at which it doesn't require additional air over what can already pass through the standard air system, there will be minimal power gain. Hence cars mildly tuned (I'd say up to around the 280bhp mark) will see very little improvement by changing the air inlet system. However, move to 300+ & the standard air system is restrictive, so replacing it with a more freely flowing system will allow the engine to produce more power.

That was meant to clarify things, but I'm not sure it'll have helped!

 

Thanks nom

I had to read that a couple of times in order to digest it, but it does make sense

From what you say it would seem that for me fitting an induction kit will simply serve to satisfy my need for that induction sound rather than being of any real performance benefit?

I do not intend having my ECU remapped or increasing boost with the likes of a Dawes device. I will simply be running 3 replacement exhaust parts with the 2 cats missing.

Perhaps I should be looking at a simpler and cheaper solution for a bit of induction roar? Maybe a Blitz cone filter or the like? I presume the panel filters actually go in the air box and will not make any difference to the sound? Actually, do I still need the air box if I had a cone filter?

Sorry... I really thought I was getting a handle on this now!

[/numpty mode off]

Matt

 

Matt, the cheapest way is just to remove the resonator from the inner wing (keeping the airbox and panel filter) as nom mentions. This will give you a little more noise, more of a meow than a roar though. Cone filters (induction kits) replace the panel filter and its airbox hence the increase in noise.

When choosing a filter go for the one with the greatest surface area, not only will it potentially flow more, but its filtration will be greater.

What you/we are aiming for is zero pressure drop before the turbo. Everything between the outside world and the turbo will cause some sort of restriction, the filter being only a part of it.

 

One advantage of an induction kit is often overlooked albeit it's not a performance related thing - it makes changing sparks on the driver side much easier cos it's much quicker to remove than the standard airbox.

 

The resonator in the wing will be there if you replace your standard air filter with an aftermarket replacement or not, ditto for the induction kit. You'll physically need to remove it/cut it off to bypass it. The scoop on the left side of the engine bay feeds air into this box which is then pushed out to the induction kit/air box.

 

may I join this one? How can I get the resonator off - do I go in through the wheel arch or does it come out somehow from within the inside of the wing. Thanks

 

You saying that removing the resonator will make any difference with an induction kit ?

 

Just to say I meant that resonator removal and uprated panel filter would be good for 300+, not that it will give you 300+

Bit like Z rated tyres are good for 150mph, but if I put them on my mums RAV4 then.....LOL

 

Jay - I am getting the hang of it now, I think!

You certainly managed to confuse me though so early on in my education

Cheers

Matt

 

No problem, sorry 'bout that

 

Jay - how do I get the resonator off please? THX

 

Just to add a bit more confusion to this thread.

I have got a hks kit on my my00 and have had 3 (yes 3) maf failures in 8 months!!! bit annoying really, but because i get good bhp/lb benefits from the kit, i keep it on...

I wash my element ever 4 months to keep the dust and muck off it and to help airflow, just wondering if i need to put something onto the element once it is washed to help protect the maf? thoughts anyone??

I'd say overall it is worth it.

sly

 

Sorry, don't know how to remove resonator, my mechanic did it for me. There was a comprehensive guide posted a few years ago, try the search facility

 

Stanners,

see the following links (don't know how to make them clickable though):

http://bbs.scoobynet.co.uk/Forum9/HTML/001387.html
http://www.scoobynet.co.uk/bbs/thread.asp?ThreadID=104071
http://www.scoobynet.co.uk/bbs/thread.asp?ThreadID=109246

Cheers,

Andy

 

Clickety click

http://bbs.scoobynet.co.uk/Forum9/HTML/001387.html

http://www.scoobynet.co.uk/bbs/threa...hreadID=104071

http://www.scoobynet.co.uk/bbs/threa...hreadID=109246

 

many thanks Guys

 

The difference between a flat panel filter and a cone filter is the greater surface area and hence lower pressure loss across it.......

 

To remove the resonator, take off the front drivers wheel and then the inner wing plastic moulding. You can then unbolt the resonator. From memory I think I cut mine at the neck with a hacksaw.
Do NOT fit an APS cold air kit to any Impreza unless you have the facility to re-map the ECU and preferably do not have to rely on the MAF. I picked up a piston within 11mls of fitting mine on a standard car. The mixture was weakened beyond belief but I did not know at the time. Subsequently ran the car for 20k mls with a Link and APS C.A.K. with no problems.

The APS CAK is now for sale.

Also worth considering is the K+N 57i.

 

Hiya john,

Thanxs for the advise, i will give you a buzz sometime and have a chat about it with you if that is ok.

sly

P.S i don't seem to be that much down on power as my last rolling road showed i had 248bhp & 287lb.

 

Cars which are on the edge of det and occasionally cross it typically are very fast indeed until they blow up.

Happy to talk, but it needs to come off or you risk your engine not just your MAF.

 

Molds, everyones gonna hate/ridicule me for this... but,take off the main filter box and ....drill half inch holes approx an inch from the bottom, you can then get hosing(similar to the pipe given in the k+n induction kit)and run that to your front towbar.You get an amazing humm when idle and you get a throatier sound, the hose will also feed cold air around the filter. go on lads...
attack!!!
wont do nothing on the performance but you get a good sound!!
martin
got a k+n on my 93wrx wagon, but this is what we did to my mates...honestly!! after all its £90 compared to nowt

 

Two observations from re reading this thread, and looking at other "induction" related threads.

1. The OEM air box etc is sufficient, unless have have a full decat and are now going to look at increasing boost, re map etc., to go for big bhp.

2. Lots and lots of people use the ITG panel filter, or the green cotton WRC panel.

I now understand why number 1 is the case after help in this thread and others. I don't understand why there are so many people doing 2 - when they just have a part decat or full and intend no further mods?

Cheers

Matt


[Edited by Molds - 4/20/2003 6:45:10 PM]