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Hey guys, great forum with a wealth of info, so thought I would introduce myself and ask a few techie questions..

I am a british expat now living in Cyprus, and I have just purchased a pristine 60,000 mile 98 Forester S/Tb (240bhp model)...

I wanted an Impreza, but way too many dodgy (badly modified and thrashed by ejits) ones out here, and the wife wanted more boot space, as I already own a ZX12R powered Lotus 7 kit car for hard driving...

Anyway, I have about £3k for some initial mods, and want to spend the money wisely on enhancing the performance...

100 octane is available at the pumps here for around 60p a litre, although 98 is more easily obtainable for a few pence less so engine mods and increased boost are well within scope at some stage..

My first thoughts are to improve the suspension (lower and adjustable) and the induction to improve charge cooling, as in the summer it hits some serious highs here, then later I can focus on things like Apexi PFC etc etc....

What recommendations would you make for the suspension, brake upgrades and induction for starters?

Would like to achieve a good everyday car, with a bit of added sleeper factor with some reasonably taught handling... say @300bhp with the ability to run stock or less for cruising or the wife driving ;)

:drive:
 

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Good choice! I have the very same model. Is yours automatic tranny?
I'd reccomend a few things before your venture into the Apexi power FC, which is one of very few options for 97/98 engines.

Get a bell mouthed downpipe, preferably without cat converter, the downpipe contains the only cat in that model, big improvement in turbo spoolup.
Since you have the good fuel, I reccomend trying a ball&spring type manual boost controller like the Turboxs unit http://www.turboxs.com/shop_prod.php?what_category=1 , or a Dawes device, and set it for about 12-13psi, if yours is the same as mine fuel cut is above 13psi, while stock boost is 10psi.

I live in the Caribbean and dont have any problems with oil and coolant temperatures, but I have made some efforts toward charge cooling, I took out the intake resonatory box inside the driver side fender, and ran a length of 3" alum piping with a 90deg bend to feed air into the stock airbox from behind the foglights, I have a K&N panel filter with the stock airbox, some time back I had a full length of 3" piping leading to a K&N pod filter located inside the fender behind the foglights, but quite frankly, the airbox method seems to work just the same and the filter in the airbox stays cleaner.

I purchased a ~2002 STI intercooler, but it needs some fabrication to be made to work with the 97/98 recirc valve setup, as you will see, the idle air control unit on the 97/98 intake manifold occupies the space that later engines had the recirc valved located, on the endtank of the intercooler, therefore I cannot fit a 99-onward intercooler+ recirc valve onto a 97/98 engine. If you are looking for an upgraded top mount intercooler, look for aftermarket items made for the 97/98, the STI intercooler of 97/98 models is not much larger than the stock unit, and you may find this is not worth the cost, also with or without actually upgrading the intercooler, you can get a much better flowing STI or aftermarket 'Y' pipe, that goes from the turbo outlet to the intercooler inlets.
I wont speak of adjustable lowered suspension upgrades because I havent done any, but I have installed a STI thicker 20mm rear sway bar, and solid steel and polyurethane swaybar links front and rear, which provide an appreciable reduction in side to side body roll on cornering. You will see that the stock rear links are quite easily flexed, and the stock front ones are quite easily broken.
Brake upgrades, you can take the minimalist approach of installing stainless steel braided brake lines and upgraded pads, which is all I have done. If you want to, you can install a current forester XT upgrade, which use a larger rotor (same size as WRX), and a caliper bracket that spaces the existing caliper further out to fit this rotor, this upgrade will fit under the stock wheels.
If you intend to change to WRX 16" wheels or 17", you can install the larger WRX rotors and 4 pot calipers, if you go to 17" or further, you can install STI brembo rotors and calipers.
 

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Discussion Starter #3
Thanks Joth

Some great info there thanks, yes mine is an Auto... Have been using autos now for some time, for round town work, they just make for a more relaxing drive... and I have my lous rep for hard driving and embarrasing the WRX owners..



:Banane01:
 

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Hi and welcome.

You should not need all the budget (to startwith anyway) but here's my top tips:
Stiffer rear anti-roll bar - either Whiteline, STi or Cusco
Stiffer front and rear drop links - Whiteline
New front anti roll bar bushes - Powerflex
Fit 17" wheels - style is purely personal (but I don't like gold on Foresters though I did on my Imprezas)
Fit late classic Impreza four pot front brakes and discs with personal preference front pads - I use Mintex and stainless steel braided lines.
Flat panel air filter from Greenstuff/K&N
Change the air intake - process known as "snorkelectomy" - 1 hours fiddling
Probably in Cyprus I would find the intercooler spray (from an STi or make your own) useful - I have one here in the Uk and its useful in traffic.
Live with those changes - total cost say £1200 for a few weeks and then see if you need to play with the engine
 

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Thanks Oldgit, I like the wheels I have on my lotus rep, OX Superleggeras as they are nice and light, so may try a set of those longer term.... gold wheels on silver car will look a bit crap like you say, so either silver, titanium, gunmetal or black I think...

Rest of the mods sound good to improve handling braking charge cooling etc, which is more important than power at first I think...

What are the thoughts on front mount intercoolers, such as paces for the impreza?
 

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You'll have to cut up the bumper alot to fit an Impreza front mount, besides very little space in the forester bumper for a front mount, theres not much cutaway for airflow either.
The only SF style bumper ive seen that would suit a front mount is this http://www.cna.ne.jp/~a_buhin/sti-forester-1_t.jpg which I have never seen in person, and certainly does not exist on all STI foresters, most look like the regular bumper but with a lower aero lip integrated into it (not stuck on)
 

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As for front mounted intercoolers I know Palatine has one in an S/Tb that he got out of an Evo (I think) so he could be a useful contact.
My wife is getting suspicious about the changes I've made so a front mounted intercooler might be a step too far ;-)
 

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Discussion Starter #8
Thanks for the info guys...



Stock intercooler looks a bit weedy for the 40 odd degrees we get in summer...

:poke:
 
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S/TB Great SUV

Hi,
I´m new in this forum.
I´ve read you own a 98 JDM S/TB. Looking at the picture i can see your engine is a Boxer Master IV so your engine actually produces 250ps (~246HP).
I have a S/TB also but 99/00 spec with a Boxer Phase II engine with 240ps but with slightly higher torque output.

As far as mods are related, you can try replacing the rear sway bar for a thicker one. I have one from an Impreza WRX (2001) which is 20mm. Standard rear sway bar is only 14mm so you´ll feel such improvement inmediatly.
As for the engine, i´m gonna tell you what i did with my former Impreza turbo 97/98 spec. I´m sure this will work because both share the same engine but with different heads+cams:
- Install a VF-34 turbo. This is the best choice because spool up is good and lag is reduced.
- Complete 3.0" Exhaust system (turbo back: downpipe, centerpipe, rear muffler).
- Motech (if budget allow, this is the best weapon).
- STI (pink) injectors.
- Uprated fuel pump.
- Free flow induction system + silicon hoses (turbo + intercooler)
- Decent BOV: you have installed the one made of plastic with 34mm inlet/outlet ports. I recall installed one from ForgeMotorsport with very good results.

I recommend you also to replace your stock clutch (excedy, Cusco) + brakes (get those from the WRX 01-up).
I did all that with 97 RON gasoline so you should go even further as you can get 100 RON.

With regard my Forester, now is almost standard and i´ve read 10psi in my gauge as max stock boost pressure. I´m not sure if this is the actual max stock boost pressure the engine can produce as i´m restricted to use 97 RON gasoline instead of the 100 RON Japanese gasoline. Because the ECU tries to to minimize engine knocking it retards timing when lower gasoline octane is used (decreasing max boost pressure also).
I´m tempted to increase boost pressure just a little bit and play with the APEXI S-AFC II as it´s known the TD04L turbo can handle 16psi without trouble; for now and due my gasoline limitation i´ll only try 2 or 3 more psi.

Good luck and enjoy that toy.
Oscar.
 
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