jase5

Hey guys, I have a ‘99 Sport and therefore my car is NA obviously and has no turbo, I’m looking to improve engine performance… am I correct in presuming the ways to increase the power of such an engine are.. improved air in/out (colder/more of it in, better flow out), improved spark and improved fuel, the 3 things that make the internal combustion engine work! I can only put in the best fuel provided by the petrol pumps and I will be upgrading the spark plugs soon, therefore, the remaining factor to improve is the air intake and exhaust.

To primarily improve looks/noise and secondly performance (slightly) I recently fitted an Afterburner Vortex Back Box. Love the look and noise and I believe that this mod alone, does, slightly improve performance at higher revs, I don’t think is a ‘placebo’ effect. I will be looking to further improve the exhaust system in the future, however, this thread concentrates on the intake.

Having recently asked advice on whether to go for an upgraded panel filter or an induction kit, the responses I had were to go for an upgraded panel filter.

Having, been a little surprised, thinking that surely induction kits are better than panel filters, I did a fair bit of research, mainly google’in ‘scoobynet’ followed by ‘panel filter’, ‘induction kit’ etc etc, and I think I’ve managed to work out the following…

Induction kits don’t provide any real gain over panel filters until your running big power, which I’m quite clearly not with my sport with back box, so I understand there is no real need for an induction kit, but would like the induction kit sound/roar if possible with a Sport!?? And think it looks better under the bonnet than the heaps of black plastic tubing and boxes that you get on the Sport, but at the same time, don’t want to replace for looks/noise if I will not gain any performance, I’m not thaattt silly lol!

I’ve read that induction kits are a risky mod if not installed correctly, by this I mean, I’ve read that all they do is suck in hot air from the engine bay and they can vibrate a hell of a lot, in turn braking mafs.

Are these the only reasons not to go for an induction kit??

If so, what about if I install and secure an induction kit sufficiently so that vibrations will not be an issue and therefore not break the maf.

And

What If I also build a heat shield or even box it up completely and feed it with cold air??

With these precautions taken, would it be ok to run an induction kit and then would an induction kit be an improvement over the standard air intake system and standard panel filter??

I know the previous points will tempt you with the response…
‘Why go for an induction kit if your going to box it up etc. as that is basically what the already boxed up panel filter is??’… True point.

Therefore instead of going through all the work to make an induction kit safe and work efficiently how about installing and securing a K&N Apollo kit which has its own shielding and case and comes with a cold air feed?

So my question is now, would either; an induction kit installed in the way I described above / a K&N Apollo kit… provide more and cooler air to my air intake than my standard panel filter??

If after all the above there really is no gain of an induction kit over a panel filter on a car so standard as mine then I’d like to at least provide a better cold air feed to the panel filter box than the standard air intake setup. On my sport the snorkel is behind the offside head light, I’ve heard on the turbos the snorkel is situated near the hole in the wing and is therefore fed cold air from the wing, this is not the case on the sport (mine at least), I do have the hole in the wing but the snorkel on mine is definitely not there, and therefore mine is not being fed cooler air from the wing but surely must be being fed much warmer/hotter air from the engine bay area behind the headlight. From the snorkel there are then a mass of black plastic pipes and boxes till the panel filter box.

Regarding a cold air feed whether it be to improve air flow to the original panel filter box or to feed an induction kit I am thinking of either taking a cold air feed through a fog light cover or through/behind the wedge near the indicator and then passing this up through the hole in the wing into the engine bay.

For an Induction kit, whether it be boxed up or within a heat shield can this cold air feed from the fog light cover simply feed the area/box that the induction kit is in?

For a K&N Apollo am I correct in thinking that the provided cold air feed can be installed in the fog light, then run up the wing and goes directly into the Apollo?

Similarly to the K&N Apollo if I was to chose to provide a better cold air feed to the standard panel filter air box could I also simply just provide a feed straight from the fog light cover to the standard panel filter box?

For the theories above regarding the K&N Apollo and standard panel filter box, the cold air feed would force cold air through the cold air feed (when the car is travelling at speed) straight into the K&N Apollo filter or panel filter box, I’m guessing this is better but is this OK as I’ve read about water or even other debris being sucked/forced through the cold air feed and then having no where else to go but getting stuck in the cold air feed itself or the Apollo air filter or panel filter box?? Would a solution to this be to have a cold air feed from the Apollo or panel filter box going into the wing and then having a cold air feed from the fog light into the wing, so that the air in the wing is colder but there is no direct route from the air outside to the filters so the air would not be forced into the filters but it would be cooler??
I very much look forward to any responses to help clear any of the above up for me, I am a noob after all, but like to think I have done some research prior to asking dumb questions, so do hope this won’t waste anyones time!

Very Many Thanks,

Jase

Terminator X

iTrader: (7)

Very hard to get more out of a n/a engine. Sell yours & buy a turbo will do the trick though

TX.

Shaks-STI

iTrader: (7)

+1 turbo car mate

morpheus1870

Don't waste any more money on the n/a, get a trubo simple.

JGSTIPRO

+1

Midlife......

iTrader: (2)

Have you tried posting on Imprezasport ??

http://www.imprezasport.net/forums/index.php?app=portal


Shaun

mart01

induction kit, no need = swap panel filter for green or pipercross (upgrade)= done.
de-cat unequal length headers = no point loss of power gained and loss of back pressure gained.
Spark plugs = ngk irrodiun keep clear tips break off.
ported throttle body= better pick up but no need.
Map = no need sports have 15% ley way on air and fuel delivery and the mapper carnt get much out of the n/a so i've being told and it would be a waste of money.
The car is your's do what you wish but i've just being honest

jh1

You,d be better saving towards a wrx. Money spent on the sport will get very little gains so not worth it

LegacySTi

iTrader: (13)

As above. save your money for a turbo..

jase5

Thanks for your replies, I'm 22 and nearly had the sport a year, was paying 150 a month wi direct line for third party fire and theft and no mods (cheapest i could get when I got the car, when I was 21)! wanted to mod so canx and now paying 250 a month wi aviva for fully comp (wont do me 3rd party) wi mods declared, ie the 'zorst, rims, prodrive spoiler, and rear sti lights and some colour coding lol, they, nor anyone else that I have found will insure me on a turbo before I'm 25, I'm 23 in November, so still have over 2 years to wait, trust me I'd much prefer to have a Turbo as your all saying, but I'd also much prefer to still drive a scooby for the mean time rather than some small engined hot hatch which would be cheaper to insure! So for the time being I want to make the most out of my sport with out spending silly money as I see there is no point, so, with the fact that I can't have a turbo (unless anyone can point me in the direction of an insurer who will insure me on one for similar money that I pay at the time being) then does any have any further knowledge to my questions above? Many thanks guys

Maz

iTrader: (34)

With respect fella I think your query has been more than answered notably in post seven by Mart. For any gains (if there are any to be had) the amount of hassle and expense is simply not worth it. The induction kit will give you a bit of noise but no gain in performance irrespective of the cold air feed. The easiest route for the cold air feed is probably from the O/S fog light.

jase5

Ok thank you, I understand, I just enjoy tinkling around and upgrading what I can, it just seems frustrating that I am forced to have a sport over a turbo due to insurance purposes and even more frustrating finding out there is little I can really 'tinker' with, with a sport !

If an induction kit will give me the noise, and it won't decrease performance and I setup a cold air feed through the fog light, then at least I can be happier knowing that the air will be colder than standard at least and maybe more of it will be taken in despite there probably being no performance increase, so long as there won't be any decrease in performance.

Thanks for your responses guys, just a shame I can't have a turbo!!

mart01

why dont you make a upgrade on brakes? use turbo fronts! mayb a centre section on the exhaust . Braided hoses. if you are not going keep the car long just make little suttle mods. if your planning on keeping it for years then mayb a v5 spoiler, a turbo bonnet. instead of waisting money on things that not going happen spend it on things that does. LOOKS BRAKES and HANDELING!!! i've found out this the hard way trust me

Paulo P

iTrader: (42)

To be honest I'd personally upgrade the brakes and suspension as mentioned above. The WRX stuff bolts straight on and I gave my old STI parts to my mate for free and they improved his sport.

Trying to tune any N/A car is costly £ for BHP, I know it's not what you want to hear but put the cash in the bank and save for a turbo model instead

gazzawrx

iTrader: (11)

there's always high lift/fast road cams, head porting, mapping, increase in fuel pressure and air flow, exhaust, better plugs, better injectors, and possibly a low blow setup but that wont be cheap.

harvey

iTrader: (48)

I have no direct experience of these cars so do not know what the successful mods are but the following may give you some ideas.
1) Port the headers/exhaust manifold. Porting is not just a matter of putting a bevel at the top of the inlet manifold. Do some research. Done properly it will show tangible gains.
2) It is unlikely a big bore exhaust will do anything for your performance but you must be fully decatted.
3) Do not fit a cone filter. Stick with the pannel. There is nothing wrong with the O/E pannel and despite glossy and often dishonest advertising claims the difference between an aftermarket pannel and the O/E will be next to nothing and some aftermarket will result in less power.
4) You could experiment with a positive air feed. ie slightly higher pressure air feed from the forward movement of the car.
5) Without the ability to alter fuel and ignition maps you will not derive best benefits from the above. I have no idea but is it possible to adjust your fuelling and ignition timing. If it is not possible then any improvements you make will be relatively small.
6) Anything you do to straighten out air flow and smooth it into the inlet manifold is a good thing.
7) Keep the hot bits hot and the cold bits cold.
8) Find a site as suggested above that specialises in the Sport because what is good on a turbo car may have no relevance on an N/A and we, in the main, here, have no knowledge of what workks, your ECU etc.

rossyboy

iTrader: (8)

This isnt very constructive, but

£3k a year to insure an Impreza Sport

harvey

iTrader: (48)

I must say I thought that too.
Shop around for insurance on a 2 litre UK 2000 or WRX.
That way you are starting at 215+ bhp a figure you are never likely to reach on any Sport no matter how much you spend.

jase5

Had already thought of the following, its simply a matter of when funds allow and how long it takes, before my age increases towards 25 and a Turbo becomes more affordable to insure:
- 4 pot front discs, rear discs
- decat centre section (as long as this will still pass mot, yeah?)
- Subtle mods made: debadged boot, de-tango’d, full crystal lights, sti rear lights, colour coded door handles, skirts, hockey sticks and wing mirrors.
- ProDrive Spolier already on!
- Currently looking for a 52D coloured Turbo Bonnet, (Pretty much at the top of my want list right now, so if anyone knows of one about, gimme a shout!)
Many thanks for your suggestions though!

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As mentioned above, brakes are on the list, and thinking lowering springs in the way of suspension as hopefully they’ll provide the car with a lower stance, which is mainly what I’m after, rather than performance which comes at a bigggger cost! Will lowering springs increase performance slightly due to lowering the center of gravity anyway? Will have to keep me eye out, anyone got any freebies going lol or any parts they’d like to donate haha! But I wanna enjoy my sport whilst I have it, I’ll start on the Turbo, once I have that lol! Money saved now, means no more tinkering with my car atm lol!

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I think most of this is probably beyond me, and don’t wanna spend silly money on getting performance out of the engine as I understand theres not a great deal you can do with the N/A I just simply wanted to upgrade the smaller parts such as the air intake, which is why I was posting to begin with lol.

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Wow, thanks very much for these suggestions!
1) Think this is way beyond tbh lol!
2) Understood, is mainly for looks and the noise, won’t fully decatting mean a failed MOT? What about a decatted centre section this would help right and still pass an MOT?
3) Ok, taken onboard, seems like such a shame after all my research and the point of this thread being to find out what would be the best possible upgrade choice in the way of air filter and getting cold air to it..
4) Will definitely be doing this, thinking through fog light through wing and into engine bay, one way or another!
5) No idea either and don’t think I really want to mess around too much with those things lol!
6) Will be taken into consideration when cold air feed project starts!
7) Will do my best!
8) Will definitely be speaking to those over at imprezasport.net!
Very many thanks!

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&

Mental isn’t it, this is the choice I have made to be able to drive around in a Scooby albeit a sport, I’d rather spend this out on my 2.0 4wd scoob than slightly less on a modded corsa, saxo, fiesta etc, with engine half the size and only front wheel drive, my scoob’s much more fun lol!!

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Regarding the spark plugs, I’ve been recommended the ngk’s, are they all irrodiun tipped? Which would be the best upgrade in the way of spark plugs then? This may end up needing to be a separate thread lol!

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Thank you all for your responses, It’s greatly appreciated! I was simply in the process of servicing my car oils, fluids, filters, etc and just wanted to know when I came to the air filter what were the options regarding upgrades etc and if they are worth it lol

mrmadcap

I’d rather spend this out on my 2.0 4wd scoob than slightly less on a modded corsa, saxo, fiesta etc, with engine half the size and only front wheel drive, my scoob’s much more fun lol!!

Sorry, but you are misguided, the above are far better than an Impreza Sport and cheaper also. With the right engine they will give an Impreza Turbo a run for their money.
Buy a hatch, put your money in the bank, play the waiting game and buy a turbo when the time is right. Throwing cash at a sport will lead to regret later on.

jase5

Any car with the ‘right engine’ will give an Impreza Turbo a run for its money, of course it will, that goes without saying.

I cannot afford the ‘right engine’ or more to the point the insurance to run a car with the ‘right engine’.

So my options are:

- Insure a slightly modded Sport, that I can enjoy spending money on to make look and sound (to a degree) like a turbo and do the odd performance upgrade here and there till I can insure a turbo, but in the mean time I can still enjoy owning, modding and driving a Scooby and gaining experience so that when I can upgrade to a Turbo, I can do so with possibly a little more knowledge of Imprezas in general.

OR

- Insure a slightly more modded smaller engined, not 4wd car, that I wouldn’t like the look of as much as the Impreza and I really don’t think I’d be able to have anything else that performance wise could out do an Impreza Sport for the same money to Insure anyway.

This is all a wasted argument anyway, as I like the Impreza hence I have one, the only reason I don’t have a turbo is because of the cost to Insure, or I would and I’m not solely wanting performance as there could may well be better performing cars possibly for cheaper to insure (I can’t see how though, as surely insurance would simply go up with performance anyway). Plus if throwing cash at my Sport gives me joy in the mean time, whats wrong with that?

Sorry if this comes across a bit strong, but was just a little put out by your comment, didn’t really expect another member to pretty much say ditch the Impreza for a hatch just because it’s not a turbo! I was thinking possibly some people might respect the fact that I’m young and am willing to pay higher insurance costs just so that I can drive a Scooby at my age even if it’s a Sport, but nvm, thanks for your thoughts anyway.